Are you an optimist or a pessimist? Put so starkly, the question has a fatuous ring. Unless you are in the grip of a bipolar disorder, you are probably optimistic about some things and pessimistic about others. Optimism tends to reign when people are imagining how their own plans will turn out. Research shows that we systematically exaggerate our chances of success, believing ourselves to be more competent and more in control than we actually are. Some 80 percent of drivers, for example, think they are better at the wheel than the typical motorist and thus less likely to have an accident. We live in a Lake Woebegon of the mind, it seems, where all the children are above average. Such “optimism bias,” as psychologists have labeled it, is hardly confined to our personal lives. In fact, as Daniel Kahneman, a Nobel laureate  in economics, and Jonathan Renshon argue in the current issue of Foreign Policy, it may help explain why hawkishness so often prevails at the national level. Wasn’t the Iraq war expected by proponents to be “fairly easy” (John McCain ) or “a cakewalk” (Kenneth Adelman)?
But when it comes to the still bigger picture — the fate of civilization, of the planet, of the cosmos — pessimism has historically been the rule. A sense that things are heading downhill is common to nearly every culture, as Arthur Herman observes in “The Idea of Decline in Western History.” The golden age always lies in the past, never in the future. It’s not hard to find a psychological explanation for this big-picture gloominess. As we age, we become aware of our powers diminishing; we dwell on the happy episodes from our past and forget the wretched ones; moving toward the grave, we are consumed by nostalgia and foreboding. What could be more natural than to project this mixture of attitudes onto history at large?
The very idea of progress, a novelty of the Enlightenment that has been in fashion only fitfully since, can grow wearisome. “Progress might have been all right once,” Ogden Nash said, “but it has gone on too long.”
You might think scientists would be the optimistic exception here. Science, after all, furnishes the model for progress, based as it is on the gradual and irreversible growth of knowledge. At the end of last year, Edge.org , an influential scientific salon, posed the questions “What are you optimistic about? Why?” to a wide range of thinkers. Some 160 responses have now been posted at the Web site. As you might expect, there is a certain amount of agenda-battling, and more than a whiff of optimism bias. A mathematician is optimistic that we will finally get mathematics education right; a psychiatrist is optimistic that we will find more effective drugs to block pessimism (although he is pessimistic that we will use them wisely). But when the scientific thinkers look beyond their own specializations to the big picture, they continue to find cause for cheer — foreseeing an end to war, for example, or the simultaneous solution of our global-warming and energy problems. The most general grounds for optimism offered by these thinkers, though, is that big-picture pessimism so often proves to be unfounded. The perennial belief that our best days are behind us is, it seems, perennially wrong.
Such reflections may or may not ease our tendency toward global pessimism. But what about our contrary tendency to be optimistic — indeed, excessively so — in our local outlook? Is that something we should, in the interests of cold reason, try to disabuse ourselves of? Optimism bias no doubt causes a good deal of mischief, leading us to underestimate the time and trouble of the projects we undertake. But the mere fact that it is so widespread in our species suggests it might have some adaptive value. Perhaps if we calculated our odds in a more cleareyed way, we wouldn’t be able to get out of bed in the morning.
A couple of decades ago, the psychologist Shelley Taylor proposed that “positive illusions” like excessive optimism were critical to mental health. People who saw their abilities and chances realistically, she noted, tended to be in a state of depression. (Other psychologists, taking a closer look at the data, countered that depressives actually show more optimism bias than nondepressives: given the way things turn out for them, they are not pessimistic enough.) And there is new evidence that optimism may in some ways be self-fulfilling. In a recently published study, researchers in the Netherlands found that optimistic people — those who assented to statements like “I often feel that life is full of promises” — tend to live longer than pessimists. Perhaps, it has been speculated, optimism confers a survival advantage by helping people cope with adversity.
But pessimism still appears to have its advantages. Another recently published paper observes that over the last three decades, the people of Denmark have consistently scored higher on life-satisfaction than any other Western nation. Why? Because, say the authors, the Danes are perennial pessimists, always reporting low expectations for the year to come. They then find themselves pleasantly surprised when things turn out rather better than expected.
Americans, too, are lowering their expectations, at least in one respect. According to the Census Bureau ’s 2007 Statistical Abstract of the United States, most college freshmen in 1970 said their primary goal was to develop a meaningful life philosophy. In 2005, by contrast, most freshmen said their primary goal was to be comfortably rich — a more modest one, it would seem, given the relative frequency of wealth and wisdom.
As for the minority still seeking a philosophy of life, the Viennese satirist Karl Kraus came up with a formula nearly a century ago that remains the perfect blend of optimism and pessimism: Things are hopeless but not serious.