2001 : WHAT QUESTIONS HAVE DISAPPEARED?

Or at least, certainly not the ones that have so far been submitted to this list, since the questions posted are proof positive that they have not disappeared at all, or at least, not altogether. Sure, some questions have their heyday for a while, and then they may disappear for many a moon. But the great question you posed -- what questions have disappeared? -- shows that they were just waiting for a question like this for someone to be reminded just how much emptier our existence would be without certain questions.

But I also think that some questions certainly have gone by the wayside for a long time, though not necessarily the ones that so far have been posed. We may ask, for instance, questions like, Has history ended?, and then go on to offer up a response of one sort or another. But when is the last time we asked, what *is* history? What different types of history are there? What makes history history, regardless of which type it is?

Or we may ask: Why have certain questions been discarded? But when's the last time anyone has asked, What is a question? What does a question do? What does a question to do us, and what do we do to it?

We may ask: How do people differ in how they think and learn? But do we still ask: What is thinking? What is learning?

Instead, we seem to take for granted that we know what history is, that we know what thinking is, that we know what learning is, when in fact if we delved a little more into these questions, we may well find that none of us hold the same views on what these rich concepts mean and how they function. Which leads me to this perspective: What *has* all but disappeared, I think, is a way of answering questions, regardless of which one is being posed, regardless of how seemingly profound or off-beat or mundane it is. I'm speaking of the kind of rigorous, exhaustive, methodical yet highly imaginative scrutiny of a Socrates or a Plato that challenged all assumptions embedded in a question, and that revealed breathtakingly new vistas and hidden likenesses between seemingly disparate entities.

Who these days takes the time and effort, much less has the critical and creative acumen, to answer questions as those I've already posed, much less such questions as ¨What is human good?¨ or ¨What is a good human?¨in the soul-stirringly visionary yet at the same time down-to-earth way they did? We need a new generation of questioners in the mold of Plato and Sorcrates, people who dare to think a bit outside the lines, who take nothing for granted when a question is posed, and who subject their scrutiny to continual examination and consideration of cogent objections and alternative ways of seeing.

CHRISTOPHER PHILLIPS is the author of ¨Socrates Cafe: A Fresh Taste of Philosophy¨, and founder-executive director of the nonprofit Society for Philosophical Inquiry.

No doubt, there are differences between women and men, some obvious and others more contentious. But arguments for inequality of worth or rights between the sexes have wholly lost intellectual respectability. Why? Because they were grounded in biologically evolved dispositions and culturally transmitted prejudices that, however strongly entrenched, could not withstand the kind of rational scrutiny to which they have been submitted in the past two centuries. Also because, more recently, the Feminist movement has given so many of us the motivation and the means to look into ourselves and recognize and fight lingering biases. Still, the battle against sexism is not over — and it may never be.

DAN SPERBER is a social and cognitive scientist at the French Centre National de la Recherche Scientifique (CNRS) in Paris. His books include Rethinking Symbolism, On Anthropological Knowledge, Explaining Culture: A Naturalistic Approach, and, with Deirdre Wilson, Relevance: Communication and Cognition.

I am going to take slight liberty with your question. With the publication a decade ago of Francis Fukuyama's justly acclaimed article The End Of History, many pundits and non-pundits assumed that historical forces and trends had been spent. The era of the "isms" was at an end; liberal democracy, market forces, and globalization had triumphed; the heavy weight of the past was attenuating around the globe.

At the start of 2001, we are no longer asking "Has History Ended?" History seems all too alive. The events of Seattle challenged the globalization behemoth; the world is no longer beating a path to internet startups; Communist and fascist revivals have emerged in several countries; the historical legacies in areas like the Balkans and the Middle East are as vivid as ever; and, as I noted in response to last year's question, much of Africa is at war. As if to remind us of our naivete, Fidel Castro and Saddam Hussein have been in "office" as long as most Americans can remember. If George II is ignorant of this history, he is likely to see it repeated.

HOWARD GARDNER, the major proponent of the theory of multiple intelligences, is Professor of Education at Harvard University and author of numerous books including The Mind's New Science and Extraordinary Minds: Portraits of Four Exceptional Individuals.

What does science have to say about the origins of love in the scheme of things? Not a lot. In fact, it is still virtually a taboo subject, just as consciousness was until very recently. However, since feelings are a major component of consciousness, it seems likely that the ontology of love is now likely to emerge as a significant question in science.

Within Christian culture, as in many other religious traditions, love has its origin as a primal quality of God and so is co-eternal with Him. His creation is an outpouring of this love in shared relationship with beings that participate in the essential creativity of the cosmos. As in the world of Shakespeare and the Renaissance Magi, it is love that makes the world go round and animates all relationships.

This magical view of the world did not satisfy the emerging perspective of Galilean science, which saw relationships in nature as law-like, obeying self-consistent logical principles of order. God may well have created the world, but he did so according to intelligible principles. It is the job of the scientist to identify these and describe them in mathematical form. And so with Newton, love turned into gravity. The rotation of the earth around the sun, and the moon around the earth, was a result of the inverse square law of gravitational attraction. It was not a manifestation of love as an attractive principle between animated beings, however much humanity remained attached to romantic feelings about the full moon. Love was henceforth banished from scientific discourse and the mechanical world-view took over.

Now science itself is changing and mechanical principles are being replaced by more subtle notions of interaction and relationships. Quantum mechanics was the first harbinger of a new holistic world of non-local connectedness in which causality operates in a much more intricate way than conventional mechanism. We now have complexity theory as well, which seeks to understand how emergent properties arise in complex systems such as developing organisms, colonies of social insects, and human brains. Often these properties are not reducible to the behavior of their component parts and their interactions, though there is always consistency between levels: that is, there are no contradictions between the properties of the parts of a complex system and the order that emerges from them. Consciousness appears to be one of these emergent properties. With this recognition, science enters a new realm.

Consciousness involves feelings, or more generally what are called qualia, the experience of qualities such as pain, pleasure, beauty, and ŠŠ. love. This presents us with a major challenge. The scientific principle of consistency between levels in systems requires that feelings emerge from some property of the component parts (e.g., neurones) that is consistent with feeling, experience. But if matter is 'dead', without any feeling, and neurones are just made of this dead matter, even though organized in a complex way, then where do feelings come from ? This is the crunch question which presents us with a hard choice. We can either say that feelings are epiphenomena, illusions that evolution has invented because they are useful for survival. Or we can change our view of matter and ascribe to the basic stuff of reality some elementary component of feeling, sentience, however rudimentary. Of course, we could also take the view that nature is not self-consistent and that miracles are possible; that something can come from nothing, such as feeling from dead, insentient matter, thus returning to the magical world-view of the early renaissance. But if we are to remain scientific, then the choice is between the other two alternatives.

The notion that evolution has invented feelings because they are useful for survival is not a scientific explanation, because it gives no account of how feelings are possible as properties that emerge in the complex systems we call organisms (i.e., consistent emergent properties of life). So we are left with the other hard choice: matter must have some rudimentary property of sentience. This is the conclusion that the mathematician/philosopher A.N. Whitehead came to in his classic, Process and Reality, and it is being proposed as a solution to the Cartesian separation of mind and matter by some contemporary philosophers and scientists. It involves a radical reappraisal of what we call 'reality'. But it does suggest a world in which love exists as something real, in accord with most peoples' experience. And goodness knows, we could do with a little more of it in our fragmented world.

BRIAN GOODWIN is a professor of biology at the Schumacher College, Milton Keynes, and the author of Temporal Organization in Cells and Analytical Physiology, How The Leopard Changed Its Spots: The Evolution of Complexity, and (with Gerry Webster) Form and Transformation: Generative and Relational Principles in Biology. Dr. Goodwin is a member of the Board of Directors of the Sante Fe Institute.

This question (or pair of questions) was on everyone's lips in the 1970s, following the oil shortage and lines at gas stations. It stimulated a lot of good thinking and good work on alternative energy sources, renewable energy sources, and energy efficiency. Although this question is still asked by many knowledgeable and concerned people, it has disappeared from the public's radar screen (or, better, television screen). Even the recent escalation of fuel prices and the electricity shortage in California have not lent urgency to thinking ahead about energy.

But we should be asking, we should be worrying, and we should be planning. A real energy crisis is closer now than it was when the question had high currency. The energy-crisis question is only part of a larger question: How is humankind going to deal in the long term with its impact on the physical world we inhabit (of which the exhaustion of fossil fuels is only a part)? Another way to phrase the larger question: Are we going to manage more or less gracefully a transition to a sustainable world, or will eventual sustainability be what's left, willy nilly, after the chaos of unplanned, unanticipated change?

Science will provide no miracles (as the Wall Street Journal, in its justification of inaction, would have us believe), but science can do a lot to ameliorate the dislocations that this century will bring. We need to encourage our public figures to lift their eyes beyond the two-, four-, and six-year time horizons of their jobs.

KENNETH FORD is a retired physicist who teaches at Germantown Friends School in Philadelphia. He is the co-author, with John Wheeler, of Geons, Black Holes, and Quantum Foam: A Life in Physics.

From the time of the Enlightenment philosophers have speculated that the remarkable advances of science would one day spill over into the realm of moral philosophy, and that scientists would be able to discover answers to previously insoluble moral dilemmas and ethical conundrums. One of the reasons Ed Wilson's book Consilience was so successful was that he attempted to revive this Enlightenment dream. Alas, we seem no closer than we were when Voltaire, Diderot, and company first encouraged scientists to go after moral and ethical questions. Are such matters truly insoluble and thus out of the realm of science (since, as Peter Medewar noted, "science is the art of the soluble")? Should we abandon Ed Wilson's Enlightenment dream of applying evolutionary biology to the moral realm? Most scientists agree that moral questions are scientifically insoluble and they have abandoned the Enlightenment dream. But not all. We shall see.

MICHAEL SHERMER is the founding publisher of Skeptic magazine, the host of the acclaimed public science lecture series at Caltech, and a monthly columnist for Scientific American. His books include Why People Believe Weird Things, How We Believe, and Denying History.

I do not, of course, mean any particular Great Central Theory. I am referring to the once-pervasive habit of relating everything that had human scale — Chinese history, the Odyssey, your mother's fear of heights — to an all-explaining principle. This principle was set forth in a short shelf of classic works and then worked to a fine filigree by close-minded people masquerading as open-minded people. The precise Great Central Theory might be, as it was in my childhood milieu, the theories of Freud. It might be Marx. It might be Levi-Strauss or, more recently, Foucault. At the turn of the last century, there was a Darwinist version going, promulgated by Francis Galton, Herbert Spencer and their ilk.

These monolithic growths had begun, I suppose, as the answers to specific questions, but then they metastasized; their adherents would expect the great central theory to answer any question. Commitment to a Great Central Theory thus became more a religious act than an intellectual one. And, as with all religions, the worldview of the devout crept into popular culture. (When I was in high school we'd say So-and-So was really anal about his locker or that What's-his-name's parents were really bourgeois.) For decades, this was what intellectual life appeared to be: Commit to an overarching explanation, relate it to everything you experienced, defend it against infidels. Die disillusioned, or, worse, die smug.

So why has this sort of question vanished? My guess is that, broadly speaking, it was a product of the Manichean worldview of the last century. Depression, dictators, war, genocide, nuclear terror — all of these lend themselves to a Yes-or-No, With-Us-or-With-Them, Federation vs. Klingons mindset. We were, to put it simply, all a little paranoid. And paranoids love a Great Key: Use this and see the single underlying cause for what seems to be unrelated and random!

Nowadays the world, though no less dangerous, seems to demand attention to the seperateness of things, the distinctiveness of questions. ''Theories of everything'' are terms physicists use to explain their near-theological concerns, but at the human scale most people care about, where we ask questions like ''why can't we dump the Electoral College?'' or ''How come Mom likes my sister better?'', the Great Central Theory question has vanished with the black-or-white arrangement of the human world.

What's next?

Three possibilities.

One, some new Great Central Theory slouches in; some of the Darwinians think they've got the candidate, and they certainly evince signs of quasi-religious commitment. (For example, as a Freudian would say you doubted Freud because of your neuroses, I have heard Darwinians say I doubted their theories because of an evolved predisposition not to believe the truth. I call this quasi-religious because this move makes the theory impregnable to evidence or new ideas.)

Two, the notion that overarching theory is impossible becomes, itself, a new dogma. I lean toward this prejudice myself but I recognize its dangers. An intellectual life that was all boutiques could be, in its way, as stultifying as a giant one-product factory.

Three, we learn from the mistakes of the last two centuries and insist that our answers always match our questions, and that the distinction between theory and religious belief be maintained.

DAVID BERREBY'S writing about science and culture has appeared in The New York Times Magazine, The New Republic, Slate, The Sciences and many other publications.

The detection of "questions that are no longer asked" is difficult. Old questions, like MacArthur's old soldiers, just fade away. Scientists and scholars in hot pursuit of new questions neither note nor mourn their passing. I regularly face a modest form of the disappearing question challenge when a textbook used in one of my classes is revised. Deletions are hard to find; they leave no voids and are more stealthy than black holes, not even affecting their surrounds. New text content stands out, while missing material must be established through careful line-by-line reading. Whether in textbooks or in life, we don't think much about what is no longer relevant.

My response to the inquiry about questions that are no longer asked is to reframe it and suggest instead a common class of missing questions, those associated with obsolete and inappropriate metaphors. Metaphor is a powerful cognitive tool, which, like all models, clarifies thinking when appropriate, but constrains it when inappropriate. Science is full of them. My professional specialties of neuroscience and biopsychology has mind/brain metaphors ranging from Locke's ancient blank slate (tabula rasa), to the more technologically advanced switchboard, and the metaphor de jour, the computer. None do justice to the brain as a soggy lump of wetware, but linger as cognitive/linguistic models. Natural selection in the realm of metaphors is slow and imperfect. Witness the reference to DNA as a "blueprint" for an organism, when Dawkins' "recipe" metaphor more accurately reflects DNA's incoding of instructions for organismic assembly.

ROBERT R. PROVINE is Professor of Psychology and Neuroscience at the University of Maryland, Baltimore County, and author of Laughter: A Scientific Investigation.

Despite Seattle and the French farmers, free market advocates of globalization have largely won — even CHina is signing up to be a major player in the international trading and growth-oriented global political economy. So it is rare to hear this question anymore, even from so-called "enterprise institutes" dedicated to protecting property rights.

The problem is, what has been won?? My concern is not with the question no-longer asked in this context, but rather with the companion question not often enough asked: "Is there any such thing as a free market"?

To be sure, markets are generally efficient ways of allocating resources and accomplishing economic goals. However, markets are notorious for leaving out much of what people really value. In different words, the market price of doing business simply excludes much of the full costs or benefits of doing business because many effects aren't measured in traditional monetary units. For example, the cost of a ton of coal isn't just the extraction costs plus transportation costs plus profit, but also real expenses to real people (or real creatures) who happen to be external to the energy market. Such "externalities" are very real to coastal dwellers trying to cope with sea level rises likely to be induced from the global warming driven by massive coal burning.

I recall a discussion at the recent international negotiations to limit emissions of greenhouse gasses in which a chieftain from the tiny Pacific island of Kiribati was being told by an OPEC supporter opposed to international controls on emissions from fossil fuels that the summed economies of all the small island states were only a trivial fraction of the global GDP, and thus even if sea level rise were to drive them out of national existence, this was "not sufficient reason to hold back to economic progress of the planet by constricting the free use of energy markets".

"We are not ungenerous", he said, so in the "unlikely event" that you were a victim of sea level rise, "we'll just pay to relocate all of you and your people to even better homes and jobs than you have now", and this, he went on, will be much cheaper than to "halt industrial growth" (THis isn't the forum to refute the nonsense that controls on emissions will halt industrial growth.) After hearing this offer, the aging and stately chieftain paused, scratched his flowing hair, politely thanked the OPEC man for his thoughtfulness and simply said, "we may be able to move, but what do I do with the buried bones of my grandfather?"

Economists refer to the units of value in cost-benefit analyses as "numeraires" — dollars per ton carbon emitted in the climate example, is the numeraire of choice for "free market" advocates. But what of lives lost per ton of emissions from intensified hurricanes, or species driven off mountain tops to extinction per ton, or heritage sites lost per ton?? Or what if global GDP indeed goes up fastest by free markets but 25% of the world gets left further behind as globally economically efficient markets expand? Is equity a legitimate numeraire too?

Therefore, while market systems seem indeed to have triumphed, it is time to phase in a new, multi-part question: "How can free markets be adjusted to value what is left out of private cost-benefit calculus but represents real value so we can get the price signals in markets to reflect all the costs and benefits to society across all the numeraires, and not simply have market prices rigged to preserve the status quo in which monetary costs to private parties are the primary condition?"

I hope the new US president soon transcends all that obligatory free market rhetoric of the campaign and learns much more about what constitutes a full market price. It is very likely he'll get an earful as he jetsets about the planet in Air Force 1 catching up on the landscapes — political and physical — of the vastly diverse countries in the world that it is time for him to visit. Many world leaders are quite worried about just what we will have won as currently defined free markets triumph.

STEPHEN H. SCHNEIDER is Professor in the Biological Sciences Department at Stanford University and the Former Department Director and Head of Advanced Study Project at the National Center for Atmospheric Research Boulder. He is internationally recognized as one of the world's leading experts in atmospheric research and its implications for environment and society. Dr. Schneider's books include The Genesis Strategy: Climate Change and Global Survival; The Coevolution Of Climate and Life and Global Warming: Are We Entering The Greenhouse Century?; and Laboratory Earth

A question no longer being asked is how to make the next step in the evolution of a democratic society. Until very recently it was widely understood that democracy was a project with many steps, whose goal was the eventual construction of a perfectly just and egalitarian society. But recently, with the well deserved collapse of Marxism, it has begun to seem that the highest stage of civilization we humans can aspire to is global capitalism leavened by some version of a bureaucratic welfare state, all governed badly by an unwieldy and corrupt representative democracy. This is better than many of the alternatives, but it is hardly egalitarian and often unjust; those of us who care about these values must hope that human ingenuity is up to the task of inventing something still better. 

It is proper that the nineteenth century idea of utopia has finally been put to rest, for that was based on a paradox, which is that any predetermined blueprint for an ideal society could only be imposed by force. It is now almost universally acknowledged that there is no workable alternative to the democratic ideal that governments get their authority by winning the consent of the governed. This means that if we are to change society, it must be by a process of evolution rather than revolution. But why should this mean that big changes are impossible? What is missing are new ideas, and a context to debate them. 

There are at least four issues facing the future of the democratic project. First, while democracy in the worlds most powerful country is perceived by many of its citizens as corrupted, there is little prospect for serious reform. The result is alienation so severe that around half of our citizens do not participate in politics. At what point, we may ask, will so few vote that the government of the United States may cease to have a valid claim to have won the consent of the governed. As the political and journalistic classes have largely lost the trust of the population, where will leadership to begin the reform that is so obviously needed come from?

A second point of crisis and opportunity is in the newly democratized states. In many of these countries intellectuals played a major role in the recent establishment of democracy. These people are not likely to go to sleep and let the World Bank tell them what democracy is.

The third opportunity is in Europe, where a rather successful integration of capitalism and democratic socialism has been achieved. These societies suffer much less from poverty and the other social and economic ills that appear so unsolvable in the US context. (And it is not coincidental that the major means of funding political campaigns in the US are illegal in most of Europe.) Walking the streets in Denmark or Holland it is possible to wonder what a democratic society that evolved beyond social democracy might look like. European integration may be only the first step towards a new kind of nation state which will give much of its sovereignty up to multinational entities, a kind of nation-as-local-government.

Another challenge for democracy is the spread of the bureaucratic mode of organization, which in most countries has taken over the administration of education, science, health and other vital areas of public interest. As any one who works for a modern university or hospital can attest to, bureaucratic organizations are inherently undemocratic. Debate amongst knowledgeable, responsible individuals is replaced by the management of perceptions and the manipulation of supposedly objective indices. As the politics of the academy begins to look more like nineteenth century Russia than 5th Century BC Athens we intellectuals need to do some serious work to invent more democratic modes of organization for ourselves and for others who work in the public interest. 

Is it not then time we "third culture intellectuals" begin to attack the problem of democracy, in both our workplaces and in our societies? Perhaps, with all of our independence, creativity, intelligence and edginess, we may find we really have something of value to contribute? 

LEE SMOLIN is a theoretical physicist; professor of physics and member of the Center for Gravitational Physics and Geometry at Pennsylvania State University; author of The Life of The Cosmos.

Different people on the Edge list seem to have chosen to understand 'questions that have disappeared' in three very different senses:

1. Questions that were once popular but have now been answered 
2. Questions that should never have been asked in the first place 
3. Questions that have disappeared although they never received a satisfactory answer.

This third meaning is, I suspect, the one intended by the organizer of the forum.  It is the most interesting of the three since it suggests real science that we should now be doing, rather than just raking over the historical coals.

The three meanings are too disparate to bring together easily, but I'll try. The popular question 'Has there been enough time for evolution to take place?'  can now confidently be answered in the affirmative.  It should never have been put in the first place since, self-evidently, we are here. But what is more interesting is that the real question that faces us is almost the exact opposite.  Why is evolution so slow, given that natural selection is so powerful?   Far from there being too little time for evolution to play with, there seems to be too much.

Ledyard Stebbins did a theoretical calculation about an extremely weak selection pressure, acting on a population of mouse-sized animals to favor the largest individuals.  His hypothetical selection pressure was so weak as to be below the threshold of detectability in field sampling studies.  Yet the calculated time to evolve elephant-sized descendants from mouse-sized ancestors was only a few tens of thousands of generations: too short to be detected under most circumstances in the fossil record.  To exaggerate somewhat, evolution could be yo-yo-ing from mouse to elephant, and back again, so fast that the changes could seem instantaneous in the fossil record.

Worse, Stebbins's calculation assumed an exceedingly weak selection pressure.  The real selection pressures measured in the field by Ford and his colleagues on lepidoptera and snails, by Endler and his colleagues on guppies, and by the Grants and their colleagues on the Galapagos finches, are orders of magnitude stronger.  If we fed into the Stebbins calculation a selection pressure as strong as the Grants have measured in the field, it is positively worrying to contemplate how fast evolution could go.  The same conclusion is indirectly suggested by domestic breeding.  We have gone from wolf to Yorkshire terrier in a few centuries, and could presumably go back to something like a wolf in as short a time.

It is indeed the case that evolution on the Galapagos archipelago has been pretty fast, though still nothing like as fast as the measured selection pressures might project.  The islands have been in existence for five million years at the outside, and the whole of their famous endemic fauna has evolved during that time.  But even the Galapagos islands are old compared to Lake Victoria.  In the less than one million years of the lake's brief lifetime, more than 170 species of the genus Haplochromis alone have evolved.

Yet the Coelacanth Latimeria, and the three genera of lungfish, have scarcely changed in hundreds of millions of years.  Surviving Lingula ('lamp shells') are classified in the same genus as their ancestors of 400 million years ago, and could conceivably interbreed with them if introduced through a time machine.  The question that still faces us is this.  How can evolution be both so fast and so leadenly slow?  How can there be so much variance in rates of evolution?  Is stasis just due to stabilizing selection and lack of directional selection?  Or is there something remarkably special going on in the (non) evolution of living fossils?  As William Blake might have written to a coelacanth: Did he who made the haplochromids make thee?

RICHARD DAWKINS is an evolutionary biologist and the Charles Simonyi Professor For The Understanding Of Science at Oxford University; Fellow of New College; author of The Selfish Gene, The Extended Phenotype , The Blind Watchmaker, River out of Eden (ScienceMasters Series), Climbing Mount Improbable, and Unweaving the Rainbow.

Contemporary linguists tend to assume in their work that subordinate clauses, such as "The boy that I saw yesterday" or "I knew what happened when she came down the steps", are an integral part of the innate linguistic endowment, and/or central features of "human speech" writ large. Most laymen would assume the same thing. However, the fact is that when we analyze a great many strictly spoken languages with no written tradition, subordinate clauses are rare to nonexistent. In many Native American languages, for example, the only way to express something like the men who were members is a clause which parses approximately as "The 'membering' men"; the facts are similar in thousands of other languages largely used orally.

In fact, even in earlier documents in today's "tall building" literary languages, one generally finds a preference for stringing simple main clauses together —she came down the steps, and I knew what happened rather than embedding them in one another along the lines of when she came down the steps, I knew what happened. The guilty sense we often have when reading English of the first half of the last millennium that the writing is stylistically somewhat "clunky" is due largely to the marginality of the subordinate clause: here is Thomas Malory in the late fifteenth century:

And thenne they putte on their helmes and departed 
and recommaunded them all wholly unto the Quene
and there was wepynge and grete sorowe
Thenne the Quene departed in to her chamber
and helde her
that no man shold perceyue here grete sorowes

Early Russian parses similarly, and crucially, so do the Hebrew Bible and the Greek of Homer.

At the time that these documents were written, writing conventions had yet to develop, and thus written language hewed closer to the way language is actually spoken on the ground. Over time, subordinate clauses, a sometime thing in speech, were developed as central features in written speech, their economy being aesthetically pleasing, and more easily manipulated via the conscious activity of writing than the spontaneous "on-line" activity of speaking. Educated people, exposed richly to written speech via education, tended to incorporate the subordinate clause mania into their spoken varieties. Hence today we think of subordinate clauses as "English", as the French do "French", and so on — even though if we listen to a tape recording of ourselves speaking casually, even we tend to embrace main clauses strung together in favor of the layered sentential constructions of Cicero.

But the "natural" state of language persists in the many which have had no written tradition. In the 1800s, various linguists casually speculated as to whether subordinate clauses were largely artifactual rather than integral to human language, with one (Karl Brugmann) even going as far as to assert that originally, humans spoke only with main clauses.

Today, however, linguistics operates under the sway of our enlightened valuation of "undeveloped" cultures, which has, healthily, included an acknowledgment of the fact that the languages of "primitive" peoples are as richly complex as written Western languages. (In fact, the more National Geographic the culture, the more fearsomely complex the language tends to be overall.) However, this sense has discouraged most linguists from treading into the realm of noting that one aspect of "complexity", subordinate clauses, is in fact not central to expression in unwritten languages and is most copiously represented in languages with a long written tradition. In general, the idea that First World written languages might exhibit certain complexities atypical of languages spoken by preliterate cultures has largely been tacitly taboo for decades in linguistics, generally only treated in passing in obscure venues.

The problem is that this could be argued to bode ill for investigations of the precise nature of Universal Grammar, which will certainly require a rigorous separation of the cultural and contingent from the encoded.

JOHN H. MCWHORTER is Assistant Professor of Linguistics at the University of California at Berkeley. He taught at Cornell University before entering his current position at Berkeley. He specializes in pidgin and creole languages, particularly of the Caribbean, and is the author of Toward a New Model of Creole Genesisand The Word on the Street : Fact and Fable About American English. He also teaches black musical theater history at Berkeley and is currently writing a musical biography of Adam Clayton Powell, Jr.

One question that has almost disappeared, but which I think should not is the old question about whether our categories of reality are discovered or constructed. In medieval times this was the debate about realism versus nominalism. Earlier this century the question flared up again in the debates about the relativistic nature of knowledge and has more recently given rise to the whole "science wars" debacle, but reading the science press today one would think the question had been finally resolved — on the side of realism. Reading the science press now one gets a strong impression that for most scientists our categories of reality are Platonic, almost God-given entities just waiting for the right mind to uncover them. This hard-nosed realist trend is evident across the spectrum of the sciences, but is particularly strong in physics, where the search is currently on for the supposed "ultimate" category of reality — strings being a favored candidate. What gets lost in all this is any analysis of the role that language plays in our pictures of reality. We literally cannot see things that we have no words for. As Einstein once said "we can only see what our theories allow us to see." I would argue that the question of what role language plays in shaping our picture of reality is one of the most critical questions in science today — and one that should be back on the agenda of every thoughtful scientiist.

Just one example should suffice to illustrate what is at stake here: MIT philosopher of science Evelyn Fox Keller has shown in her book Secrets of Life, Secrets of Death (and elsewhere) the primary role played by language in shaping theories of genetics. Earlier this century physicists like Max Delbruck and Erwin Schrodinger started to have a philosophical impact on the biological sciences, which henceforth became increasingly "physicized." Just as atoms were seen as the ultimate constituents of matter so genes came to be seen as the ultimate constituents of life — the entities in which all power and control over living organisms resided. What this metaphor of the "master molecule" obscured was th role played by the cytoplasm in regulating the function and activation of genes. For half a century study of the cytoplasm was virtually ignored because genetics were so fixed on the idea of the gene as the "master colecule." Sure much good work on genetics was done, but important areas of biological function were also ignored. And are still being ignored by the current "master molecule" camp — the evolutionary psychologists, who cannot seem to see anything but through the prism of genes.

Scientists (like all other humans) can only see reality as their language and their metaphors allow them to see it. This is not to say that scientists "make up" their discoveries, only to point out that language plays a critical role in shaping the way we categorize, and hence theorize, the world around us. Revolutions in science are not just the result of revolutions in the laboratory or at theorists blackboards, they are also linguistic revoluttions. Think of words like inertia, energy, momentum — words which did not have any scientific meaning before the seventeenth century. Or words like quantum, spin, charm and strange, which have only had scientific meaning science the quantum revolution of the early twentieth century. Categories of reality are not merely discovered — they are also constructed by the words we use. Understanding more deeply the interplay between the physical world and human language is, I believe, one of the major tasks for the future of science.

MARGARET WERTHEIM is the author of Pythagoras Trousers, a history of the relationship between physics and religion; and The Pearly Gates of Cyberspace: A History of Space from Dante to the Internet. She is a research associate to the American Museum of Natural History in NY and a fellow of the Los Angeles Institute for the Humanities. She is currently working on a documentary about "outsider physics."

With the success of molecular biology explaining the mechanisms of life we have lost sight of the question one level up. We do not have any good answers at a more systems level of what it takes for something to be alive. We can list general necessities for a system to be alive, but we can not predict whether a given configuration of molecules will be alive or not. As evidence that we really do not understand what it takes for something to be alive, we have not been able to build machines that are alive.

Everything else that we understand leads to machines that capitalize on that understanding — machines that fly, machines that run, machines that calculate, machines that make polymers, machines that communicate, machines that listen, machines that play games. We have not built any machines that live.

RODNEY A. BROOKS is director of the MIT Artificial Intelligence Laboratory and Chairman of iRobot Corporation. He builds robots.

The road of knowledge is littered with old questions, but by their very nature, none of them stands out above all others. The diversity of thoughtful responses given on the Edge forum, which just begin to scratch the surface, illustrates how progress happens. The evolution of knowledge is a Schumpterian process of creative destruction, in which weeding out the questions that no longer merit attention is an integral part of formulating better questions that should. Forgetting is a vital part of creation.

Maxwell once worried that the second law of thermodynamics could be violated by a demon who could measure the velocity of individual particles and separate the fast ones from the slow ones, and use this to do work. Charlie Bennet showed that that this is impossible, because to make a measurement the demon has to first put her instruments in a known state.

This involves erasing information. The energy needed to do this is more than can be gained. Thus, the fact that forgetting takes work is essential to the second law of thermodynamics. Why is this relevant? As Gregory Bateson once said, the second law of thermodynamics is the reason that it is easier to mess up a room than it is to clean it. Forgetting is an essential part of the process of creating order. Asking the right questions is the most important part of the creative process. There are lots of people who are good at solving problems, fewer who are good at asking questions.

Around the time I took my qualifying examination in physics, someone showed me the test that Lord Rayleigh took when he graduated as senior wrangler from Cambridge in 1865. I would have failed it. There were no questions on thermodynamics, statistical mechanics, quantum mechanics, nuclear physics, particle physics, condensed matter, or relativity, i.e. no questions covering most of what I had learned.

However, the classical mechanics questions, which comprised most of the bets, were diabolically hard. Their solution involved techniques that are no longer taught, and that a modern physicist would have to work hard to recreate. Of course, in a field like philosophy this would not have surprised me — it just hadn't occurred to me that this was as true for physics as well. The physicists in Rayleigh's generation presumably worked just as hard, and knew just as many things. They just knew different things. After overcoming the shock of how much had seemingly been lost, I rationalized my ignorance with the belief that what I was taught was more useful than what Rayleigh was taught. Whether as a culture or as individuals, to learn new things, we have to forget old things. The notion of what is useful is constantly evolving.

The most important questions evolve through time as people understand little bits and pieces, and view them from different angles in the attempt to solve them. Each question is replaced by a new one that is (hopefully) better framed than its antecedant. Reflecting on those that have been cast aside is like sifting through flotsam on a beach, and asking what it tells us. Is there a common thread that might give us a clue to posing better questions in the future?

When we examine questions such as "What is a vital force?", "How fast is the earth moving?", "Does God exist?", "Have we seen the end of science?", "Has history ended?", "Can machines think?", there are some common threads. One is that we never really understood what these questions meant in the first place. But these questions (to varying degrees) have been useful in helping us to formulate better, more focused questions. We just have to turn loose of our pet ideas, and make a careful distinction between what we know and what we only think we know, and try to be more precise about what we are really asking.

I would be curious to hear more discussion about the common patterns and the conclusions to be drawn from the questions that have disappeared.

J. DOYNE FARMER, one of the pioneers of what has come to be called chaos theory, is McKinsey Professor, Sante Fe, Institute, and the co founder and former co-president of Prediction Company in Santa Fe, New Mexico.

Progress in the domain that Marvin Minsky once characterized as "making machines do things that would be considered intelligent if done by people" has not been as dramatic as its founders might once have hoped, but the penetration of machine cognition into everyday life (from the computer that plays chess to the computer that determines if your toast is done) has been broad and deep. We now the term "intelligent" to refer to the kind of helpful smartness embedded in such objects. So the language has shifted and the question has disappeared. But until recently, there was a tendency to limit appreciation of machine mental prowess to the realm of the cognitive. In other words, acceptance of artificial intelligence came with a certain "romantic reaction." People were willing to accept that simulated thinking might well be deemed thinking, but simulated feeling was not feeling. Simulated love could never be love.

These days, however, the realm of machine emotion has become a contested terrain. There is research in "affective computing" and in robotics which produces virtual pets and digital dolls — objects that present themselves as experiencing subjects. In artificial intelligence's "essentialist" past, researchers tried to argue that the machines they had built were "really" intelligent. In the current business of building machines that self-present as "creatures," the work of inferring emotion is left in large part to the user. The new artificial creatures are designed to push our evolutionary buttons to respond to their speech, their gestures, and their demands for nurturance by experiencing them as sentient, even emotional. And people are indeed inclined to respond to creatures they teach and nurture by caring about them, often in spite of themselves. People tell themselves that the robot dog is a program embodied in plastic, but they become fond of it all the same. They want to care for it and they want it to care for them.

In cultural terms, old questions about machine intelligence has given way to a question not about the machines but about us: What kind of relationships is it appropriate to have with a machine? It is significant that this question has become relevant in a day-to-day sense during a period of unprecedented human redefinition through genomics and psychopharmacology, fields that along with robotics, encourage us to ask not only whether machines will be able to think like people, but whether people have always thought like machines

SHERRY TURKLE is a professor of the sociology of science at MIT. She is the author of Life on the Screen: Identity in the Age of the Internet; The Second Self: Computers and the Human Spirit; and Psychoanalytic Politics: Jacques Lacan and Freud's French Revolution.

The moment of birth used to be attended by an answer to a nine-month mystery: girl or boy? Now, to anyone with the slightest curiosity and no mystical scruples, simple, non-invasive technology can provide the answer from an early stage of pregnancy. With both of our children, we chose to know the answer (in the UK about half of parents want to know), and I suspect the likelihood of the question continuing to be asked will diminish rapidly.

What's interesting is this is the first of many questions about the anticipated child that will soon not be asked. These will range from the trivial (eye colour, mature height) to the important (propensity to certain diseases and illnesses). The uneasiness many people still have about knowing the sex of the child suggests that society is vastly unprepared for the pre-birth answers to a wide range of questions.

LANCE KNOBEL is a managing director of Vesta Group, an Internet and wireless investment company based in London. He was formerly head of the programme of the World Economic Forum's Annual Meeting in Davos and Editor-in-Chief of World Link.

Some questions are so rarely asked that we are astonished anyone would ask them at all. The entire world seems to agree that knowing mathematics is the key to something important, they just forget what. Benjamin Franklin asked this question in 1749 while thinking about what American schools should be like and concluded that only practical mathematics should be taught. The famous mathematician G.H. Hardy asked this question (A Mathematicians's Apology) and concluded that while he loved the beauty of mathematics there was no real point teaching it to children.

Today, we worry about the Koreans and Lithuanians doing better than us in math tests and every "education president" asserts that we will raise math scores, but no one asks why this matters. Vague utterances about how math teaches reasoning belie the fact that mathematicicans do everyday reasoning particularly better than anyone else. To anyone who reads this and still is skeptical, I ask: what is the Quadratic Formula? You learned it in ninth grade, you couldn't graduate high school without it. When was the last time you used it? What was the point of learning it?

ROGER SCHANK is the Chairman and Chief Technology Officer for Cognitive Arts and has been the Director of the Institute for the Learning Sciences at Northwestern University since its founding in 1989. One of the world's leading Artificial Intelligence researchers, he is books include: Dynamic Memory: A Theory of Learning in Computers and People , Tell Me a Story: A New Look at Real and Artificial Memory, The Connoisseur's Guide to the Mind, and Engines for Education.

Most Americans, even (or, perhaps, especially) educated Americans, seem to believe that all people are basically the same ‹ we have the same innate abilities and capacities, and only hard work and luck separates those who are highly skilled from those who are not. But this idea is highly implausible. People differ along every other dimension, from the size of their stomachs and shoes to the length of their toes and tibias. They even differ in the sizes of their brains. So, why shouldn't they also differ in their abilities and capacities? Of course, the answer is that they do. It's time to acknowledge this fact and take advantage of it.

In my view, the 21st century is going to be the "Century of Personalization." No more off-the-rack drugs: Gene and proteonomic chips will give readouts for each person, allowing drugs to be tailored to their individual physiologies. No more off-the-rack clothes: For example, you'll stick your feet in a box, lasers will measure every aspect of them, and shoes will be custom-made according to your preferred style. Similarly, no more off-the-rack teaching.

Specifically, the first step is to diagnose individual differences in cognitive abilities and capacities, so we can play to a given person's strengths and avoid falling prey to his or her weaknesses. But in order to characterize these differences, we first need to understand at least the broad outlines of general mechanisms that are common to the species.

All of us have biceps and triceps, but these muscles differ in their strength. So too with our mental muscles. All of us have a short-term memory, for example (in spite of how it may sometimes feel at the end of the day), and all of us are capable storing information in long-term memory. Differences among people in part reflect differences in the efficacy of such mechanisms. For example, there are at least four distinct ways that visual/spatial information can be processed (which I'm not going to go into here), and people differ in their relative abilities on each one. Presenting the same content in different ways will invite different sorts of processing, which will be more or less congenial for a given person.

But there's more to it than specifying mechanisms and figuring out how well people can use them (as daunting as that is). Many of the differences in cognitive abilities and capacities probably reflect how mechanisms work together and when they are recruited. Understanding such differences will tell us how to organize material so that it goes down smoothly. For example, how--for a given person-should examples and general principles be intermixed?

And, yet more. We aren't bloodless brains floating in vats, soaking up information pumped into us. Rather, it's up to us to decide what to pay attention to, and what to think about. Thus, it's no surprise that people learn better when they are motivated. We need to know how a particular student should be led to use the information during learning. For example, some people may "get" physics only when it's taught in the context of auto mechanics.

All of this implies that methods of teaching in the 21st Century will be tightly tied to research in cognitive psychology and cognitive neuroscience. At present, the study of individual differences is almost entirely divorced from research on general mechanisms. Even if this is remedied, it's going to be a challenge to penetrate the educational establishment and have this information put to use. So, the smart move will probably be to do an end-run around this establishment, using computers to tutor children individually outside of school. This in turn raises the specter of another kind of Digital Divide. Some of us may in fact still get off-the-rack education.

Finally, I'll leave aside another set of questions no one seems to be seriously asking: What should be taught? And should the same material be taught to everyone? You can imagine why this second question isn't being asked, but it's high time we seriously considered making the curriculum relevant for the 21st Century.

STEPHEN M. KOSSLYN, a full professor of psychology at Harvard at age 34, is a researcher focusing primarily on the nature of visual mental imagery. His books include Image and Mind, Ghosts in the Mind's Machine, Wet Mind: The New Cognitive Neuroscience, Image and Brain: The Resolution of the Imagery Debate, and Psychology: The Brain, the Person, the World.

This can be elaborated by the following anecdote, from an interview (2.99) with Herbert York:

"Donald Hornig, who was head of PSAC [President's Science Advisory Committee, during the Johnson Administration] was not imaginative. I can give you an example of this. I was very enthusiastic about getting a picture of the other side of the moon. And there were various ways of doing it, sooner or later. And I argued with Hornig about it and he said, 'Why? It looks just like this side.' And it turned out it didn't. But nevertheless, that was it, and that's the real Hornig. 'Why are you so enthused about the other side of the moon? The other side of the moon looks just like this side, why would you be so interested to see it?'"

GEORGE DYSON, a historian among futurists, has been excavating the history and prehistory of the digital revolution going back 300 years. His most recent book is Darwin Among the Machines.

My colleagues in the fashionable fields of string theory and quantum gravity advertise themselves as searching desperately for the 'Theory of Everything", while their experimental colleagues are gravid with the "God Particle", the marvelous Higgson which is the somewhat misattributed source of all mass. (They are also after an understanding of the earliest few microseconds of the Big Bang.) As Bill Clinton might remark, it depends on what the meaning of "everything" is. To these savants, "everything" means a list of some two dozen numbers which are the parameters of the Standard Model. This is a set of equations which already exists and does describe very well what you and I would be willing to settle for as "everything". This is why, following Bob Laughlin, I make the distinction between "everything" and "every thing". Every thing that you and I have encountered in our real lives, or are likely to interact with in the future, is no longer outside of the realm of a physics which is transparent to us: relativity, special and general; electromagnetism; the quantum theory of ordinary, usually condensed, matter; and, for a few remote phenomena, hopefully rare here on earth, our almost equally cut-and-dried understanding of nuclear physics. [Two parenthetic remarks: 1) I don't mention statistical mechanics only because it is a powerful technique, not a body of facts; 2) our colleagues have done only a sloppy job so far of deriving nuclear physics from the Standard Model, but no one really doubts that they can.]

I am not arguing that the search for the meaning of those two dozen parameters isn't exciting, interesting, and worthwhile: yes, it's not boring to wonder why the electron is so much lighter than the proton, or why the proton is stable at least for another 35 powers of ten years, or whether quintessence exists. But learning why can have no real effect on our lives, spiritually inspiring as it would indeed be, even to a hardened old atheist like myself.

When I was learning physics, half a century ago, the motivation for much of what was being done was still "is quantum theory really right?" Not just QED, though the solution of that was important, but there were still great mysteries in the behavior of ordinary matter--like superconductivity, for instance. It was only some twenty years later that I woke up to the fact that the battle had been won, probably long before, and that my motivation was no longer to test the underlying equations and ideas, but to understand what is going on. Within the same few years , the molecular biology pioneers convinced us we needed no mysterious "life force" to bring all of life under the same umbrella. Revolutions in geology, in astrophysics, and the remarkable success of the Standard Model in sorting out the fundamental forces and fields, leave us in the enviable position I described above: given any problematic phenomenon, we know where to start, at least. And nothing uncovered in string theory or quantum gravity will make any difference to that starting point.

Is this Horgan's End of Science? Absolutely not. It's just that the most exciting frontier of science no longer lies at the somewhat sophomoric — or quasi-religious — level of the most "fundamental" questions of "what are we made of?" and the like; what needs to be asked is "how did all this delightful complexity arise from the stark simplicity of the fundamental theory?" We have the theory of every thing in any field of science you care to name, and that's about as far as it gets us. If you like, science is now almost universally at the "software" level; the fundamental physicists have given us all the hardware we need, but that doesn't solve the problem, in physics as in every other field. It's a different game, probably a much harder one in fact, as it has often been in the past; but the game is only begun. 

PHILIP W. ANDERSON is a Nobel laureate physicist at Princeton and one of the leading theorists on superconductivity. He is the author of A Career in Theoretical Physics, and Economy as a Complex Evolving System.

The distinctive Amnesty International arched sticker, with a burning candle surrounded by a swoosh of barbed wire, seemed to adorn every college dorm-room door, beat up Honda Accord, and office bulletin board when I started college in the late '80s at Fordham University. Human rights was the "in" cause. So, we all joined Amnesty and watched our heroes including Bruce Springsteen, Sting, and Peter Gabriel sing on the "Human Rights Now" tour (brought to you, of course, by Reebok).

As quickly as it took center stage, however, human rights seemed to fall off the map. Somewhere in the mid-90s, something stole our fire and free time, perhaps it was the gold rush years of the Internet or the end of the Cold War. The wild spread of entrepreneurship and capitalism may have carried some democracy along with it. Yet just because people are starting companies and economic markets are opening up doesn't mean that there are fewer tortures, rapes, and murders for political beliefs. (These kinds of false perceptions may stem from giving places like China "Most Favored Nation" status).

Youth inspired by artists created the foundation of Amnesty's success in the '80s, so maybe a vacuum of activist artists is to blame for human rights disappearing from the collective consciousness. Would a homophobic, misogynistic, and violent artist like Eminem ever take a stand for anyone other than himself? Could anyone take him seriously if he did? Britney Spears' fans might not have a problem with her dressing in a thong at the MTV Music Awards but how comfortable would they be if she addressed the issue of the rape, kidnapping, and torture of young women in Sierra Leone?

Of course, you don't have to look around the world to find human-rights abuses. Rodney King and Abner Louima taught us that human rights is an important and pressing issue right in our backyard. (Because of these examples, some narrow-minded individuals may see is as only a race specific issue.) One bright spot in all of this, however, is that the technology that was supposed to create a Big Brother state, like video cameras, is now being used to police Big Brother himself. (Check out witness.org and send them a check — or a video camera — if you have the means.)

Eleanor Roosevelt considered her fight to create the Universal Declaration of Human Rights her greatest accomplishment. How ashamed would she be that 50 years has elapsed since her battle, and now, no one seems to care.

JASON McCABE CALACANIS is Editor and Publisher of Silicon Alley Daily; The Digital Coast Weekly, Silicon Alley Reporter and Chairman CEO, Rising Tide Studios.

The sudden increase in digital information, or bits, in our everyday lives has destroyed any question of permanence or scarcity of those bits. Just consider the example of e-mail.

Years ago when you first got online, you were excited to get e-mail, right? So every day, the big question when you logged in was, Will I have any e-mail? The chirpy announcement that "You've got mail!" actually meant something, since sometimes you didn't have mail.

Today there's no question. There's no such thing as no mail. You don't have to ask; you DO have mail. If it's not the mail you want (from friends or family), it's work-related mail or, worse, spam. Our inboxes may soon be so flooded with spam that we look for entirely different ways to use e-mail.

The death of that question, "Do I have e-mail?" has brought us a new, more interesting question as a result: "What do I do with all this e-mail?" More generally, what do we do with all these bits(e-mail, wireless messages, websites, Palm Pilot files, Napster downloads)? This is the question that will define our relationship with digital technology in coming years.

MARK HURST, founder of Internet consulting firm Creative Good, is widely credited for popularizing the term "customer experience" and the methodology around it. Hurst has worked since the birth of the Web to make Internet technology easier and more relevant to its "average" users. In 1999, InfoWorld magazine named Hurst "Netrepreneur of the Year", saying that "Mark Hurst has done more than any other individual to make Web-commerce sites easier to use." Over 39,000 people subscribe to his Good Experience newsletter, available for free at goodexperience.com or update@goodexperie nce.com.

The question that has appeared this year is "What questions (plural) have disappeared and why?" Countless questions have disappeared, of course, but for relatively few reasons.

The most obvious vanishings are connected to the passing of time. No one asks anymore "Who's pitching tomorrow for the Brooklyn Dodgers?" or "Who is Princess Diana dating now?"

Other disappearances are related to the advance of science and mathematics. People no longer seriously inquire whether Jupiter has moons, whether DNA has two or three helical strands, or whether there might be integers a, b, and c such that a^3 + b^3 = c^3.

Still other vanished queries are the result of changes in our ontology, scientific or otherwise. We've stopped wondering, "What happened to the phlogiston?" or "How many witches live in this valley?"

The most interesting lacunae in the erotetic landscape, however, derive from lapsed assumptions, untenable distinctions, incommensurable mindsets, or superannuated worldviews that in one way or another engender questions that are senseless or, at least, much less compelling than formerly. "What are the election's exact vote totals" comes to mind.

Now that I've clarified to myself the meaning of "What questions have disappeared and why?" I have to confess that I don't have any particularly telling examples. (Reminds me of the joke about the farmer endlessly elucidating the lost tourist's query about the correct road to some hamlet before admitting, "Don't reckon that I know.")

JOHN ALLEN PAULOS, bestselling author, mathematician, and public speaker is professor of mathematics at Temple University in Philadelphia. In addition to being the author of a number of scholarly papers on mathematical logic, probability, and the philosophy of science, Dr. Paulos books include Innumeracy - Mathematical Illiteracy and Its Consequences, A Mathematician Reads the Newspaper, and Once Upon a Number.

This question was at the heart of heated debates for decades during the recently past century, and it was at the ambitious origins of the Artificial Intelligence adventure. It had profound implications not only for science, but also for philosophy, technology, business, and even theology. In the 50's and 60's, for instance, it made a lot of sense to ask the question whether one day a computer could defeat an international chess master, and if it did, it was assumed that we would learn a great deal about how human thought works. Today we know that building such a machine is possible, but the reach of the issue has dramatically changed. Nowadays not many would claim that building such a computer actually informs us in an interesting way about what human thought is and how it works. Beyond the (indeed impressive) engineering achievements involved in building such machines, we got from them little (if any) insight into the mysteries, variability, depth, plasticity, and richness of human thought. Today, the question "do computers think?" has become completely uninteresting and it has disappeared from the cutting edge academic circus, remaining mainly in the realm of pop science, Hollywood films, and video games.

And why it disappeared?

It disappeared because it was finally answered with categorical responses that stopped generating fruitful work. The question became useless and uninspiring, ... boring. What is interesting, however, is that the question disappeared with no single definitive answer! It disappeared with categorical "of-course-yes" and "of-course-not" responses. Of-course-yes people, in general motivated by a technological goal (i.e., "to design and to build something") and implicitly based on functionalist views, built their arguments on the amazing ongoing improvement in the design and development of hardware and software technologies. For them the question became uninteresting because it didn't help to design or to build anything anymore. What became relevant for of-course-yes people was mainly the engineering challenge, that is, to actually design and to build computers capable of processing algorithms in a faster, cheaper, and more flexible manner. (And also, for many, what became relevant was to build computers for human activities and purposes). Now when of-course-yes people are presented with serious problems that challenge their view, they provide the usual response: "just wait until we get better computers" (once known as the wait-until the-year-2000 argument). On the other hand there were the of-course not people, who were mainly motivated by a scientific task (i.e., "to describe, explain, and predict a phenomenon"), which was not necessarily technology-driven. They mainly dealt with real-time and real-world biological, psychological, and cultural realities. These people understood that most of the arrogant predictions made by Artificial Intelligence researchers in the 60's and 70's hadn't been realized because of fundamental theoretical problems, not because of the lack of powerful enough machines. They observed that even the simplest everyday aspects of human thought, such as common sense, sense of humor, spontaneous metaphorical thought, use of counterfactuals in natural language, to mention only a few, were in fact intractable for the most sophisticated machines. They also observed that the nature of the brain and other bodily mechanisms that make thinking and the mind possible, were by several orders of magnitude, way more complex than what it was thought during the hey-days of Artificial Intelligence. Thus for of course-not people the question whether computers think became uninteresting, since it didn't provide insights into a genuine understanding of the intricacies of human thinking. Today the question is dead. The answer had become a matter of faith.

RAFAEL E. NÚÑEZ, currently at the Department of Psychology of the University of Freiburg, is a research associate of the University of California, Berkeley. He has worked for more than a decade on the foundations of embodied cognition, with special research into the nature and origin of mathematical concepts. He has published in several languages in a variety of areas, and has taught in leading academic institutions in Europe, the United States, and South America. He is the author (with George Lakoff) of Where Mathematics Comes From: How the Embodied Mind Brings Mathematics into Being; and co-editor (with Walter Freeman) of Reclaiming Cognition: The Primacy of Action, Intention, and Emotion.

Speculation about the possibility of a "plurality of worlds" goes back at least as far as Epicurus in the fourth century BC. Admittedly, Epicurus' definition of a "world" was closer to what we would currently regard as a solar system — but he imagined innumerable such spheres, each containing a system of planets, packed together. "There are," he declared, "infinite worlds both like and unlike this world [i.e., solar system] of ours."

The same question was subsequently considered by astronomers and philosophers over the course of many centuries; within the past half century, the idea of the existence of other planets has become a science fiction staple, and people have started looking for evidence of extraterrestrial civilizations. Like Epicurus, many people have concluded that there must be other solar systems out there, consisting of planets orbiting other stars. But they didn't know for sure. Today, we do.

The first "extrasolar" planet (ie, beyond the solar system) was found in 1995 by two Swiss astronomers, and since then another 48 planets have been found orbiting dozens of nearby sun-like stars. This figure is subject to change, because planets are now being found at an average rate of more than one per month; more planets are now known to exist outside the solar system than within it. Furthermore, one star is known to have at least two planets, and another has at least three. We can, in other words, now draw maps of alien solar systems — maps that were previously restricted to the realm of science fiction.

The discovery that there are other planets out there has not, however, caused as much of a fuss as might have been expected, for two reasons. First, decades of Star Trek and its ilk meant that the existence of other worlds was assumed; the discovery has merely confirmed what has lately become a widely-held belief. And second, none of these new planets has actually been seen. Instead, their existence has been inferred through the tiny wobbles that they cause in the motion of their parent stars. The first picture of an extrasolar planet is, however, probably just a few years away. Like the first picture of Earth from space, it is likely to become an iconic image that once again redefines the way we as humans think about our place in the universe.

Incidentally, none of these new planets has a name yet, because the International Astronomical Union, the body which handles astronomical naming, has yet to rule on the matter. But the two astronomers who found the first extrasolar planet have proposed a name for it anyway, and one that seems highly appropriate: they think it should be called Epicurus.

TOM STANDAGE is technology correspondent at The Economist in London and author of the books The Victorian Internet and The Neptune File, both of which draw parallels between episodes in the history of science and modern events. He has also written for the Daily Telegraph, The Guardian, Prospect, and Wired.He is married and lives in Greenwich, England, just down the hill from the Old Royal Observatory.

In 1957, a few years after he co-discovered the double helix, Francis Crick proposed a very famous hypothesis. It states that "once 'information' has passed into protein it cannot get out again. In more detail, the transfer of information from nucleic acid to nucleic acid, or from nucleic acid to protein may be possible, but transfer from protein to protein, or from protein to nucleic acid is impossible." After it had proven to form the foundation of molecular biology, he later called this hypothesis the "Central Dogma" of biology.

In the last years of the last millennium, Crick's dogma fell. The reason? Direct protein-to-protein information transfer was found to be possible in a class of proteins called "prions." With the aid of a catalyst, prions (short for "proteinaceous infectious particles") cause another molecule of the same class to adopt an infectious shape like their own simply through contact. Thus, prions are an important and only recently discovered mechanism for the inheritance of information through means other than DNA. Such an important discovery merited a recent Nobel Prize for Stanley Prusiner, who doggedly pursued the possibility of a rogue biological entity replicating without the assistance of genes against a back-drop of resistance and disbelief among most of his colleagues. Further testimony to the significance of prions comes from the current BSE crisis in Europe. Now that we know how they work, prions — and the diseases they cause — may begin popping up all over the place.

ROBERT AUNGER is an anthropologist studying cultural evolution, both through the now much-maligned method of fieldwork in nonwestern societies, and the application of theory adapted from evolutionary biology. He is at the Department of Biological Anthropology at the University of Cambridge, and the editor of Darwinizing Culture: The Status of Memetics as a Science.

They cordoned off the area and brought in disposal experts to defuse the bomb, but it turned out to be full of — sawdust. The Population Bomb is truly a dud, although this news and its implications have yet fully to sink into the general consciousness.

Ideas can become so embedded in our outlook that they are hard to shake by rational argument. As a Peace Corps Volunteer working in rural India in the 1960s, I vividly remember being faced with multiple uncertainties about what might work for the modernization of India. There was only one thing I and my fellow development workers could all agree on: India unquestionably would experience mass famine by the 1980s at the latest. For us at the time this notion was an eschatological inevitability and an article of faith.

For 35 years since those days, India has grown in population by over a million souls a month, never failing to feed itself or earn enough to buy the food it needs (sporadic famine conditions in isolated areas, which still happen in India, are always a matter of communications and distribution breakdown).

Like so many of the doomsayers of the twentieth century, we left crucial factors out of our glib calculations. First, we failed to appreciate that people in developing countries will behave exactly like people in the rest of the world: as they improve their standard of living, they have fewer children. In India, the rate of population increase began to turn around in the 1970s, and it has declined since. More importantly, we underestimated the capacity of human intelligence to adapt changing situations.

Broadly speaking, instead of a world population of 25 or 30 billion, which some prophets of the 1960s were predicting, it now looks as though the peak of world population growth might be reached within 25 to 40 years at a maximum of 8.5 billion (just 2.5 billion above the present world population). Even without advances in food technology, the areas of land currently out of agricultural production in the United States and elsewhere will prevent starvation. But genetic technologies will increase the quantities and healthfulness of food, while at the same time making food production much more environmentally friendly. For example, combining gene modification with herbicides will make it possible to produce crops that induce no soil erosion. New varieties will requires less intensive application of nitrogen fertilizers and pesticides. If genetic techniques can control endemic pests, vast areas of Africa could be brought into productive cultivation.

There will be no way to add 2.5 billion people to the planet without environmental costs. Some present difficulties, such as limited supplies of fresh water in Third World localities, will only get worse. But these problems will not be insoluble. Moreover, there is not the slightest chance that population growth will in itself cause famine. What will be fascinating to watch, for those who live long enough to witness it, will be how the world copes with an aging, declining population, once the high-point has been reached.

The steady evaporation of the question, "When will overpopulation create worldwide starvation?", has left a gaping hole in the mental universe of the doomsayers. They have been quick to fill it with anxieties about global warming, cellphones, the ozone hole, and Macdonaldization. There appears to be a hard-wired human propensity to invent threats where they cannot clearly be discovered. Historically, this has been applied to foreign ethnic groups or odd individuals in a small-scale society (the old woman whose witchcraft must have caused village children to die). Today's anxieties focus on broader threats to mankind, where activism can mix fashionable politics with dubious science. In this respect alone, the human race is not about to run out of problems. Fortunately, it also shows no sign of running out of solutions.

DENIS DUTTON, founder and editor of the innovative Web page Arts & Letters Daily (www.cybereditions.com/aldaily/), teaches the philosophy of art at the University of Canterbury, New Zealand and writes widely on aesthetics. He is editor of the journal Philosophy and Literature, published by the Johns Hopkins University Press. Professor Dutton is a director of Radio New Zealand, Inc.

Metaphysical questions. 

Metaphysical answers haven't disappeared: the new agers are full of them, and so are the old religionists. 

Cosmological questions haven't disappeared: but scientists press them as real questions about the very physical universe. 

But the old Platonic questions about the nature of the good and the form of beauty — they went away when we weren't looking. They won't be back.

JAMES J. O'DONNELL, Professor of Classical Studies and Vice Provost for Information Systems and Computing at the University of Pennsylvania, is the author of Avatars of the Word: From Papyrus to Cyberspace.

The detection of "questions that are no longer asked" is difficult. Old questions, like MacArthur's old soldiers, just fade away. Scientists and scholars in hot pursuit of new questions neither note nor mourn their passing. I regularly face a modest form of the disappearing question challenge when a textbook used in one of my classes is revised. Deletions are hard to find; they leave no voids and are more stealthy than black holes, not even affecting their surrounds. New text content stands out, while missing material must be established through careful line-by-line reading. Whether in textbooks or in life, we don't think much about what is no longer relevant.

My response to the inquiry about questions that are no longer asked is to reframe it and suggest instead a common class of missing questions, those associated with obsolete and inappropriate metaphors. Metaphor is a powerful cognitive tool, which, like all models, clarifies thinking when appropriate, but constrains it when inappropriate. Science is full of them. My professional specialties of neuroscience and biopsychology has mind/brain metaphors ranging from Locke's ancient blank slate (tabula rasa), to the more technologically advanced switchboard, and the metaphor de jour, the computer. None do justice to the brain as a soggy lump of wetware, but linger as cognitive/linguistic models. Natural selection in the realm of metaphors is slow and imperfect. Witness the reference to DNA as a "blueprint" for an organism, when Dawkins' "recipe" metaphor more accurately reflects DNA's incoding of instructions for organismic assembly.

ROBERT R. PROVINE is Professor of Psychology and Neuroscience at the University of Maryland, Baltimore County, and author of Laughter: A Scientific Investigation.

It seems to me we’ve surrendered the notion of the sacred to those who only mean to halt the evolution of culture. Things we call "sacred" are simply ideologies and truths so successfully institutionalized that they seem unquestionable. For example, the notion that sexual imagery is bad for young people to see — a fact never established by any psychological or anthropological study I’ve come across — is accepted as God-ordained fact, and used as a fundamental building block to justify censorship. (Meanwhile, countless sitcoms in which parents lie to one another are considered wholesome enough to earn "G" television ratings.)

A politician’s claim to be "God-fearing" is meant to signify that he has priorities greater than short-term political gain. What most people don’t realize is that, in the Bible anyway, God-fearing is a distant second to God-loving. People who were God-fearing only behaved ethically because they were afraid of the Hebrew God’s wrath. This wasn’t a sacred relationship at all, but the self-interested avoidance of retaliation.

Today, it seems that no place, and — more importantly — no time is truly sacred. Our mediating technologies render us available to our business associates at any hour, day or night. Any moment spent thinking instead of spending, or laughing instead of working is an opportunity missed. And the more time we sacrifice to production and consumption, the less any alternative seems available to us.

One radical proposal to combat the contraction of sacred time was suggested in the book of Exodus, and it's called the Sabbath. What if we all decided that for one day each week, we would refrain from buying or selling anything? Would it throw America into a recession? Maybe the ancients didn't pick the number seven out of a hat. Perhaps they understood that human beings can only immerse themselves in commerce for six days at a stretch before losing touch with anything approaching the civil, social, or sacred.

DOUGLAS RUSHKOFF is the author of Coercion, Media Virus, Playing the Future, Ecstasy Club. Professor of Virtual Culture, New York University.

Questions...

We ask many questions ...

...about our species, our gender, our friends, lovers and ourselves, the mystery who each of us is and where in the ant hill the intelligence lies, if each ant has no clue.

We search for the variations amongst a set, try to define the set in its limits and borders against other sets, look for analogies, anomalies and statistical outliers....

There is in fact an almost universal algorithm, like cats stalking their prey, to makes sense of our nature by boundary conditions, alas compiled with spotty statistics and messy heuristics, gullible souls, political machinations, cheats, lies and video tape, in short: human nature. We search and probe, the literate digerati confer virtually, each wondering about the other, each looking at their unique sets of parents, and the impossibility to imagine them in the act of procreation.

In other words, we still have no idea what-so-ever who we really are, what mankind as a whole is all about. We have mild inclinations on where we have been, sort of, and contradictory intentions on where we may be headed, kind of, but all in all, we are remarkably clue-free.

But that question at least need no longer be asked and has indeed vanished after this:

Even when they had way too much to drink, pigs don´t turn into men.

KAI KRAUSE is currently building a research lab dubbed "Byteburg" in a thousand year old castle above the Rhein river in the geometric center of Europe. He asked not to be summed up by previous accomplishments, titles or awards.

Some scientific questions cannot be resolved, but rather are dissolved, and vanish once we begin to better understand their terms.

This is often the case for "definitional questions". For instance, what is the definition of life? Can we trace a sharp boundary between what is living and what is not living? Is a virus living? Is the entire earth a living organism? It seems that our brain predisposes us to ask questions that require a yes or no answer. Moreover, as scientists, we'd like to keep our mental categories straight and, therefore, we would like to have neat and tidy definitions of the terms we use. However, especially in the biological sciences, the objects of reality do not conform nicely to our categorical expectations. As we delve into research, we begin to realize that what we naively conceived of as a essential category is, in fact, a cluster of loosely bound properties that each need to be considered in turn (in the case of life: metabolism, reproduction, autonomy, homeostasy, etc..). Thus, what was initially considered as a simple question, requiring a straightforward answer, becomes a complex issue or even a whole domain of research. We begin to realize that there is no single answer, but many different answers depending on how one frames the terms of the question. And eventually, the question is simply dropped. It is not longer relevant.

I strongly suspect that one of today's hottest scientific question,s the definition of consciousness, is of this kind. Some scientists seem to believe that what we call consciousness is an essence of reality, a single coherent phenomenon that can be reduced to a single level such as a quantum property of microtubules. Another possibility, however, that consciousness is a cluster of properties that, most of the time, cohere together in awake adult humans. A minimal list probably includes the ability to attend to sensory inputs or internal thoughts, to make them available broadly to multiple cerebral systems, to store them in working memory and in episodic memory, to manipulate them mentally, to act intentionally based on them, and in particular to report them verbally. As we explore the issue empirically, we begin to find many situations (such as visual masking or specific brain lesions) in which those properties break down. The neat question "what is consciousness" dissolves into a myriad of more precise and more fruitful research avenues.

Any biological theory of consciousness, which assumes that consciousness has evolved, implies that "having consciousness" is not an all-or-none property. The biological substrates of consciousness in human adults are probably also present, but only in partial form, in other species, in young children or brain-lesioned patients. It is therefore a partially arbitrary question whether we want to extend the use of the term "consciousness" to them. For instance, several mammals, and even very young human children, show intentional behavior, partially reportable mental states, some working memory ability — but perhaps no theory of mind, and more "encapsulated" mental processes that cannot be reported verbally or even non-verbally. Do they have consciousness, then? My bet is that once a detailed cognitive and neural theory of the various aspects of consciousness is available, the vacuity of this question will become obvious.

STANISLAS DEHAENE, researcher at the Institut National de la Santé, studies cognitive neuropsychology of language and number processing in the human brain; author of The Number Sense: How Mathematical Knowledge Is Embedded In Our Brains.

The moral, intellectual, physical and social improvement of the human race was a hot topic of the Enlightenment. It helped shape the American and French revolutions. Creating the "New Soviet Man" was at the heart of the Russian revolution — that's what justified the violence.

A central theme of Lyndon Johnson's Great Society was not just that human misery could be alleviated. It was that core human problems like crime could be fixed by the government eliminating root causes like want.

That's all gone.

We now barely trust government to teach kids to read.

JOEL GARREAU, the cultural revolution correspondent of The Washington Post, is a student of global culture, values, and change whose current interests range from human networks and the transmission of ideas to the hypothesis that the '90s — like the '50s — set the stage for a social revolution to come. He is the author of the best-selling books Edge City: Life on the New Frontier and The Nine Nations of North America, and a principal of The Edge City Group, which is dedicated to the creation of more liveable and profitable urban areas worldwide.

I am taking the liberty of sending two questions. (After all, the people on the list like to push the boundaries.)

"Have We Seen the End of Science?"

John Horgan announced the end of science in his book of the same title. Almost weekly the most spectacular advances are being announced and intriguing questions being asked in fields such as biology and physics. The answer was always a resounding no; now nobody asks the question.

"Will the Internet Stock Bubble Burst?"

We certainly know the answer to that one now.

On February 22, 2000 I gave a talk at the Century Association in NYC titled "Modern Finance and Computers". One of the topics that i covered was "will the internet stock bubble burst?" I said it was a classic bubble and would end in the usual way. I cited the example of an Fall, 1999 IPO for VA Linux. This was a company that had a market capitalization of 10 billion dollars at the end of the first day even though it had never shown a profit and was up against competitors such as Dell and IBM.

The NASDAQ reached its high on March 10, 2000, and the internet sector collapsed a couple of weeks later. The high for VA Linux in 2000 was $247;yesterday it closed below $10.

JOSEPH F. TRAUB is the Edwin Howard Armstrong Professor of Computer Science at Columbia University and External Professor at the Santa Fe Institute. He was founding Chairman of the Computer Science Department at Columbia University from 1979 to 1989, and founding chair of the Computer Science and Telecommunications Board of the National Academy of Sciences from 1986 to 1992. From 1971 to 1979 he was Head of the Computer Science Department at Carnegie-Mellon University. Traub is the founding editor of the Journal of Complexity and an associate editor of Complexity. A Festschrift in celebration of his sixtieth birthday was recently published. He is the author of nine books including the recently published Complexity and Information.

"... can there really be fossil sea-shells in the mountains of Kentucky, hundreds of miles from the Atlantic coast? "

This question about questions may be a useful way to differentiate "science" from "not-science"; questions really do disappear in the former in a way, or at least at a rate, that they don't in the latter.

A question that has disappeared: can there really be fossil sea-shells in the mountains of Kentucky, hundreds of miles from the Atlantic coast?

I came across this particular question recently when reading Thomas Jefferson's 'Notes on the State of Virginia'; he devotes several pages to speculation about whether the finds in Kentucky really were sea-shells, and, if so, how they could have ended up there. Geologists could, today, tell him.

"...from what source do governments get their legitimate power?"

Perhaps another question dear to Jefferson's heart has also disappeared: from what source do governments get their legitimate power? In 1780, this was a real question, concerning which reasonable people gave different answers: 'God,' or 'the divine right of Kings,' or 'heredity,' or 'the need to protect its citizens.' By declaring as 'self evident' the 'truth' that 'governments derive their just power from the consent of the governed,' Jefferson was trying to declare that this question had, in fact, disappeared. I think he may have been right.

DAVID POST is Professor of Law at Temple University, and Senior Fellow at The Tech Center at George Mason University, with an interest in questions of (and inter-connections between) Internet law, complexity theory, and the ideas of Thomas Jefferson.

The first was the Enlightenment. Hobbes claimed the brutishishness of man in a state of nature called for a governmental Leviathan. Rousseau's concept of the noble savage led him to call for the abolition of property and the predominance of the "general will." Adam Smith justified market capitalism by saying that it is not the generosity but the self-interest of the baker that leads him to give us bread. Madison justified constitutional government by saying that if people were angels, no government would be necessary, and if angels were to govern people, no controls on government would be necessary. The young Marx's notion of a "species character" for creativity and self-expression led to "From each according to his ability"; his later belief that human nature is transformed throughout history justified revolutionary social change.

The second period was the 1960s and its immediate aftermath, when Enlightenment romanticism was revived. Here is an argument the US Attorney General, Ramsay Clark, against criminal punishment: "Healthy, rational people will not injure others ... they will understand that the individual and his society are best served by conduct that does not inflict injury. ... Rehabilitated, an individual will not have the capacity-cannot bring himself-to injure another or take or destroy property." This is, of course, an empirical claim about human nature, with significant consequences for policy.

The discussion came to an end in the 1970s, when even the mildest non romantic statements about human nature were met with angry denunciations and accusations of Nazism. At the century's turn we have an unprecedented wealth of data from social psychology, ethnography, behavioral economics, criminology, behavioral genetics, cognitive neuroscience, and so on, that could inform (though of course, not dictate) policies in law, political decision-making, welfare, and so on. But they are seldom brought to bear on the issues. In part this is a good thing, because academics have been known to shoot off their mouths with half-baked or crackpot policy proposals. But since all policy decisions presuppose some hypothesis about human nature, wouldn't it make sense to bring the presuppositions into the open so they can be scrutinized in the light of our best data?

STEVEN PINKER is professor in the Department of Brain and Cognitive Sciences at MIT; director of the McDonnell-Pew Center for Cognitive Neuroscience at MIT; author of Language Learnability and Language Development, Learnability and Cognition, The Language Instinct , How the Mind Works, and Words and Rules.

The reason this question is dead is because traditional Skinnerianism, which viewed rats and pigeons as furry and feathered black boxes, guided by simple principles of reinforcement and punishment, is theoretically caput. It can no longer account for the extraordinary things that animals do, spontaneously.

Thus, we now know that animals form cognitive maps of their environment, compute numerosities, represent the relationships among individuals in their social group, and most recently, have some understanding of what others know.

The questions for the future, then, are not "Do animals think?", but "What precisely do they think about, and to what extent do their thoughts differ from our own?"

MARC D. HAUSER is an evolutionary psychologist, and a professor at Harvard University where he is a fellow of the Mind, Brain, and Behavior Program. He is a professor in the departments of Anthropology and Psychology, as well as the Program in Neurosciences. He is the author of The Evolution of Communication, and Wild Minds: What AnimalsThink.

This question bit the dust after a brief but busy life; it is entirely a second-half-of the-20th-century question. Had it been asked before the 20th century, it would have been phrased differently: "heredity" instead of "genes." But it wasn't asked back then, because the answer was obvious to everyone. Unfortunately, the answer everyone gave — yes! — was based on erroneous reasoning about ambiguous evidence: the difference in behavior between the pauper and the prince was attributed entirely to heredity. The fact that the two had been reared in very different circumstances, and hence had had very different experiences, was overlooked. 

Around the middle of the 20th century, it became politically incorrect and academically unpopular to use the word "heredity"; if the topic came up at all, a euphemism, "nature," was used in its place. The fact that the pauper and the prince had been reared in very different circumstances now came to the fore, and the behavioral differences between them was now attributed entirely to the differences in their experiences. The observation that the prince had many of the same quirks as the king was now blamed entirely on his upbringing. Unfortunately, this answer, too, was based on erroneous reasoning about ambiguous evidence. 

That children tend to resemble their biological parents is ambiguous evidence; the fact that such evidence is plentiful — agreeable parents tend to have agreeable kids, aggressive parents tend to have aggressive kids, and so on — does not make it any less ambiguous. The problem is that most kids are reared by their biological parents. The parents have provided both the genes and the home environment, so the kids' heredity and environment are correlated. The prince has inherited not only his father's genes but also his father's palace, his father's footmen, and his father's Lord High Executioner (no reference to living political figures is intended). 

To disambiguate the evidence, special techniques are required — ways of teasing apart heredity and environment by controlling the one and varying the other. Such techniques didn't begin to be widely used until the 1970s; their results didn't become widely known and widely accepted until the 1990s. By then so much evidence had piled up that the conclusion (which should have been obvious all along) was incontrovertible: yes, genes do influence human behavior, and so do the experiences children have while growing up. 

(I should point out, in response to David Deutsch's contribution to the World Question Center, that no one study, and no one method, can provide an answer to a question of this sort. In the case of genetic influences on behavior, we have converging evidence — studies using a variety of methods all led to the same conclusion and even agreed pretty well on the quantitative details.)

Though the question has been answered, it has left behind a cloud of confusion that might not disappear for some time. The biases of the second half of the 20th century persist: when "dysfunctional" parents are found to have dysfunctional kids, the tendency is still to blame the environment provided by the parents and to overlook the fact that the parents also provided the genes. 

Some would argue that this bias makes sense. After all, they say, we knowhow the environment influences behavior. How the genes influence behavior is still a mystery — a question for the 21st century to solve. But they are wrong. They know much less than they think they know about how the environment influences behavior. 

The 21st century has two important questions to answer. How do genes influence human behavior? How is human behavior influenced by the experiences a child has while growing up?

JUDITH RICH HARRIS is a writer and developmental psychologist; co-author ofThe Child: A Contemporary View Of Development; winner of the 1997 George A. Miller Award for an outstanding article in general psychology, and author ofThe Nurture Assumption: Why Children Turn Out The Way They Do.

This is a question that the ancients asked, and one that crops up a few times in 20th century philosophical discussions. When it is mentioned, it is usually as an example of a problem that looks to be both deep and in principle insoluble. Unsurprisingly, then, it seems to have fallen by the scientific, cosmological and philosophical waysides. But sometimes I wonder whether it really is insoluble (or senseless), or whether science may one day surprise us by finding an answer.

ANDY CLARK is Professor of Philosophy and Cognitive Science at the University of Sussex, UK. He was previously Director of the Philosophy/Neuroscience/Psychology Program at Washington University in St. Louis. He is the author of Microcognition: Philosophy, Cognitive Science and Parallel Distributed Processing, Associative Engines, and Being There: Putting Brain, Body and World Together Again.

During the early 1980s, I had the wonderful fortune to spend a great deal of time with Richard Feynman, and our innumerable conversations extended over a very broad range of topics (not always physics!). At that time, I had just finished re-reading his wonderful book, The Character of Physical Law, and wanted to discuss an interesting question with him, not directly addressed by his book:

Why is our sense of beauty and elegance such a useful tool for discriminating between a good theory and a bad theory?

And a related question:

Why are the fundamental laws of the universe self-similar?

Over lunch, I put the questions to him.

"It's goddam useless to discuss these things. It's a waste of time," was Dick's initial response. Dick always had an immediate gut-wrenching approach to philosophical questions. Nevertheless, I persisted, because it certainly was to be admitted that he had a strong intuitive sense of the elegance of fundamental theories, and might be able to provide some insight rather than just philosophizing. It was also true that this notion was a successful guiding principle for many great physicists of the twentieth century including Einstein, Bohr, Dirac, Gell-Mann, etc. Why this was so, was interesting to me.

We spent several hours trying to get at the heart of the problem and, indeed, trying to determine if it was even a true notion rather than some romantic representation of science.

We did agree that it was impossible to explain honestly the beauties of the laws of nature in a way that people can feel, without their having some deep understanding of mathematics. It wasn't that mathematics was just another language for physicists, it was a tool for reasoning by which you could connect one statement with another. The physicist has meaning to all his phrases. He needs to have a connection of words to the real world.

Certainly, a beautiful theory meant being able to describe it very simply in terms of fundamental mathematical quantities. "Simply" meant compression into a small mathematical expression with tremendous explanatory powers, which required only a finite amount of interpretation. In other words, a huge number of relationships between data are concisely fit into a single statement. Later, Murray Gell-Mann expressed this point well, when he wrote, "The complexity of what you have to learn in order to be able to read the statement of the law is not really very great compared to the apparent complexity of the data that are being summarized by that law. That apparent complexity is partly removed when the law is formed."

Another driving principle was that the laws of the universe are self similar, in that there are connections between two sets of phenomena previously thought to be distinct. There seemed to be a beauty in the inter-relationships fed by perhaps a prejudice that at the bottom of it all was a simple unifying law.

It was easy to find numerous examples from the history of modern science that fit within this framework (Maxwell's equations for electromagnetism, Einstein's general-relativistic equations for gravitation, Dirac's relativistic quantum mechanics, etc.,), but Dick and I were still working away at the fringes of the problem. So far, all we could do was describe the problem, find numerous examples, but we could not answer what provided the feeling for great intuitive guesses.

Perhaps, our love of symmetries and patterns, are an integral part of why would embrace certain theories and not others. For example, for every conservation law, there was a corresponding symmetry, albeit sometimes these symmetries would be broken. But this led us to another question: Is symmetry inherent in nature or is it something we create? When we spoke of symmetries, we were referring to the symmetry of the mathematical laws of physics, not to the symmetry of objects commonly found in nature. We felt that symmetry was inherent in nature, because it was not something that we expected to find in physics. Another psychological prejudice was our love for patterns. The simplicity of the patterns in physics were beautiful. This does not mean simple in action ­ the motion of the planets and of atoms can be very complex, but the basic patterns underneath are simple. This is what is common to all of our fundamental laws.

It should be noted that we could also come up with numerous examples where one's sense of elegance and beauty led to beautiful theories that were wrong. A perfect example of a mathematically elegant theory that turned out to be wrong is Francis Crick's 1957 attempt at working out the genetic coding problem (Codes without Commas). It was also true that there were many examples of physical theories that were pursued on the basis of lovely symmetries and patterns, and that these also turned out to be false. Usually, these were false because of some logical inconsistency or the crude fact that they did not agree with experiment.

The best that Dick and I could come up with was an unscientific response, which is, given our fondness for patterns and symmetry, we have a prejudice — that nature is simple and therefore beautiful.

Since that time, the question has disappeared from my mind, and it is fun thinking about it again, but in doing scientific research, I now have to concern myself with more pragmatic questions.

AL SECKEL is acknowledged as one of the world's leading authorities on illusions. He has given invited lectures on illusions at Caltech, Harvard, MIT, Berkeley, Oxford University, University of Cambridge, UCLA, UCSD, University of Lund, University of Utrecht, and many other fine institutions. Seckel is currently under contract with the Brain and Cognitive Division of the MIT Press to author a comprehensive treatise on illusions, perception, and cognitive science.

Until this summer this was the most common question at Silicon Valley parties, at bus stops, conferences and grocery stores. Everyone had a business model, none planned to make money, all focused on the exit strategy. 

The euphoria attracted a despicable kind carpetbagger, one who wanted nothing more than money, and had a disdain for technology. All of a sudden technology was out of fashion in Silicon Valley.

Now that the dotcom crash seems permanent, entrepreneurs are looking for real ways to make money. No more vacuous "business models." VCs are hunkering down for a long haul. The average IQ of Silicon Valley entrepreneurs is zooming to its former stratospheric levels. There's a genuine excitement here now, but if you ask what the business model is you're going to get a boring answer.

Silicon Valley goes in cycles. Downturns are a perfect time to dig in, listen to users, learn what they want, and create the technology that scratches the itch, and plan on selling it for money. 

DAVE WINER, CEO UserLand Software, Inc.
http://www.userland.com/

The disappearance of this question isn't only a trace of the deletion of the left. It is also a measure of our loss of faith in secular redemption. We don't look forward anymore to radical transformation.

Perhaps it's a result of a century of disappointments: from the revolution of 1917 to Stalin and the fall of communism; from the Spanish Civil War to Franco; from Mao's long march to Deng's proclamation that to get rich is glorious. Perhaps it's a result of political history. But there was more that had to do with psychological transformation. Remember Norman O. Brown's essay, "The place of apocalypse in the life of the mind"? Remember R. D. Laing's turn on breakdown as breakthrough? Remember the fascination with words like 'metamorphosis' and 'metanoia'?

Maybe we're just getting older and all too used to being the people we are. But I'd like to think we're getting wiser and less naive about the possibility of shedding our pasts overnight.

It's important to distinguish between political liberalism on the one hand and a faith in discontinuous transformation on the other. If we fail to make this distinction, then forgetting about the revolution turns (metanoically) into the familiar swing to the right. Old radicals turn reactionary. If we're less dramatic about our beliefs, if we're more cautious about distinguishing between revolutionary politics and evolutionary psychology, then we'll retain our faith in the dream that we can do better. Just not overnight.

p.s. Part of the passion for paradigms and thier shiftings may derive from displaced revolutionary fervor. If you yearn for transfiguration, but can't find it in religion or politics, then you'll seek it elsewhere, like the history of science.

p.p.s. There is one place where talk of transformation is alive and kicking, if not well: The executive suite. The business press is full of books about corporate transformation, re-engineering from a blank sheet of paper, reinvention from scratch. Yes, corporate America is feeling the influence of the sixties as boomers reach thte board room. And this is not a bad thing. For, just as the wisdom to distinguish between revolutionary politics and evolutionary psychology can help us keep the faith in marginal improvements in the human condition, so the tension between greying warriors for change and youthful stalwarts of the status quo will keep us from lurching left or right.

JAMES OGILVY is co-founder and managing director of Global Business Network; taught philosophy at Yale and Williams; served as director of research for the Values and Lifestyles Program at SRI International; author of Many Dimensional Man, and Living without a Goal.

This question is no longer asked, not because the question has been answered (although I happen to believe the answer is e to the i pi) but because the search for knowledge about the spiritual world has shifted focus as a result of science and maths cornering all the physical and numerical answers. Along with "Did Adam have a navel?" and "Did Jesus' mother give birth parthenogenetically?", this question is no longer asked by anyone of reasonable intelligence. Those who would in the past have searched for scientific support for their spiritual ideas have finally been persuaded that this is a demeaning use for human brainpower and that by moving questions about the reality of spiritual and religious ideas into the same category as questions about mind (as opposed to brain) they will retain the respect of unbelievers and actually get nearer to an understanding of the sources of their preoccupations.

As an addendum, although I wasn't asked I would like also to answer the question "What questions should disappear and why?"

The one question that should disappear as soon as possible ­ and to a certain extent scientists are to blame for the fact that it is still asked ­ is: What is the explanation for astrology/UFOs/clairvoyance/telepathy/any other 'paranormal' phenomenon you care to name?

This question is still asked because scientists and science educators have failed to get over to the public the fact that there is only one method of explaining phenomena ­ the scientific method. Therefore, anything that people are puzzled by that has not been explained either doesn't exist or there isn't yet enough evidence to prove that it does. But still I get the impression that for believers in these phenomena there are two types of explanatory system ­ science and nonscience (you can pronounce the latter 'nonsense' if you like). When you try to argue with these people by pointing out that there isn't sufficient repeatable evidence even to begin to attempt an explanation in scientific terms, they just say that this particular phenomenon doesn't require that degree of stringency. When the evidence is strong enough to puzzle scientists as well as nonscientists, they'll begin to devise explanations ­ scientific explanations.

There's a good example of how this works currently with the interest taken in St John's wort as a possible treatment for depression. Once there was enough consistent evidence to suggest that there might be an effect, clinical trials were planned and are now under way. Interestingly, an indication that there might be a genuine effect comes from a substantial body of information suggesting that there are adverse drug interactions between St John's wort and immunosuppressive drugs taken by transplant patients. Once an 'alternative' remedy actually causes harm as well as having alleged benefits, it's claimed effects are more likely to be genuine. One argument against most of the quack remedies around, such as homoeopathy, is that they are entirely safe (although this is seen as a recommendation, by the gullible.)

The demand that phenomena that are not explainable in scientific terms should be accepted on the basis of some other explanation similar to the argument you might care to use with your bank manager that there is more than one type of arithmetic. Using his conventional accounting methods he might think your account is overdrawn but you would argue that, although the evidence isn't as strong as his method might require, you believe you still have lots of money in your account and therefore will continue writing cheques. (As like as not, this belief in a positive balance in your account will be based on some erroneous assumption ­ for example, that you still have a lot of blank cheques left in your chequebook.)

KARL SABBAGH is a television producer who has turned to writing. Among his television programs are "Skyscraper" ­ a four-hour series about the design and construction of a New York skyscraper; "Race for the Top" ­ a documentary about the hunt for top quark; and "21st Century Jet" ­ a five part series following Boeing's new 777 airliner from computer design to entry into passenger service.He is the author of six books including Skyscraper, 21st Century Jet, and A Rum Affair .

Three in four entering collegians today deem it "very important" or "essential" that they become "very well-off financially." Most adults believe "more money" would boost their quality of life. And today's "luxury fever" suggests that affluent Americans and Europeans are putting their money where their hearts are. "Whoever said money can't buy happiness isn't spending it right," proclaimed a Lexus ad. But the facts of life have revealed otherwise.

Although poverty and powerlessness often bode ill for body and spirit, wealth fails to elevate well-being. Surveys reveal that even lottery winners and the super rich soon adapt to their affluence. Moreover, those who strive most for wealth tend, ironically, to live with lower well-being than those focused on intimacy and communal bonds. And consider post-1960 American history: Average real income has doubled, so we own twice the cars per person, eat out two and a half times as often, and live and work in air conditioned spaces. Yet, paradoxically, we are a bit less likely to say we're "very happy." We are more often seriously depressed. And we are just now, thankfully, beginning to pull out of a serious social recession that was marked by doubled divorce, tripled teen suicide, quadrupled juvenile violence, quintupled prison population, and a sextupled proportion of babies born to unmarried parents. The bottom line: Economic growth has not improved psychological morale or communal health.

DAVID G. MYERS is a social psychologist at Hope College (Michigan) and author, most recently, of The American Paradox: Spiritual Hunger in an Age of Plenty and of A Quiet World: Living with Hearing Loss.