"Physics and everything we know in the world around us may really be tied to processes whose fundamental existence is not here around us, but rather exists in some distant bounding surface like some thin hologram, which by virtue of illuminating it in the right way can reproduce what looks like a 3-dimensional world. Perhaps our three dimensional world is really just a holographic illumination of laws that exist on some thin bounding slice, like that thin little piece of plastic, that thin hologram. It's an amazing idea, and I think is likely to be where physics goes in the next few years or in the next decade, at least when one's talking about quantum gravity or quantum string theory."
"There are going to be things that meet those conditions that are not interestingly computational by anybody's standards, and there are things that are going to fail to meet the standards, which nevertheless you see are significantly like the things that you want to consider computational. So how do you deal with that? By ignoring it, by ignoring the issue of definition, that's my suggestion. Same as with life! You don't want to argue about whether viruses are alive or not; in some ways they're alive, in some ways they're not. Some processes are obviously computational. Others are obviously not computational. Where does the computational perspective illuminate? Well, that depends on who's looking at the illumination."
"As a theoretical physicist, my main concern is space, time and cosmology. The metaphor about information and computation is interesting. There are some people in physics who have begun to talk as if we all know that what's really behind physics is computation and information, who find it very natural to say things like anything that's happening in the world is a computation, and all of physics can be understood in terms of information. There's another set of physicists who have no idea what those people are talking about. And there's a third set — and I'm among them — who begin by saying we have no idea what you're talking about, but we have reasons why it would be nice if it was useful to talk about physics in terms of information."
"Something else has happened with computers. What's happened with society is that we have created these devices, computers, which already can register and process huge amounts of information, which is a significant fraction of the amount of information that human beings themselves, as a species, can process. When I think of all the information being processed there, all the information being communicated back and forth over the Internet, or even just all the information that you and I can communicate back and forth by talking, I start to look at the total amount of information being processed by human beings — and their artifacts — we are at a very interesting point of human history, which is at the stage where our artifacts will soon be processing more information than we physically will be able to process."
"I work on developing an understanding of biological complexity and how we can create it, because the limits of software engineering have been clear now for two decades. The biggest programs anyone can build are about ten million lines of code. A real biological object — a creature, an ecosystem, a brain — is something with the same complexity as ten billion lines of code. And how do we get there?"
"What else is there? Sex and physics."
"Silicon-based life and dust-based life are fiction and not fact. I use them as examples to illustrate an abstract argument. The examples are taken from science-fiction but the abstract argument is rigorous science. The abstract concepts are valid, whether or not the examples are real. The concepts are digital-life and analog-life. The concepts are based on a broad definition of life. For the purposes of this discussion, life is defined as a material system that can acquire, store, process, and use information to organize its activities. In this broad view, the essence of life is information, but information is not synonymous with life. To be alive, a system must not only hold information but process and use it. It is the active use of information, and not the passive storage, that constitutes life."
"For the last twenty years, I have found myself on the inside of a revolution, but on the outside of its resplendent dogma. Now that the revolution has not only hit the mainstream, but bludgeoned it into submission by taking over the economy, it's probably time for me to cry out my dissent more loudly than I have before."
"As providing an insight into the nature of reality, and the nature of the physical universe, this whole area is really fascinating. I've thought a lot about it over the years, and I'm still undecided as to whether nature could never permit such a crazy thing, or whether yes, these entities, these wormholes, or some other type of gravitational system do at least in principle exist, and in principle one could visit the past, and we have to find some way of avoiding the paradox. Maybe the way is to give up free will. Maybe that's an illusion. Maybe we can't go back and change the past freely."