Malcolm Gladwell is the author of bestselling books Blink and The Tipping Point, and is a staff writer for The New Yorker.

Several years ago, on a flight from New York to California, I had the good fortune to sit next to a psychologist named Dan Gilbert. He had a shiny bald head, an irrepressible good humor, and we talked (or, more accurately, he talked) from at least the Hudson to the Rockies--and I was completely charmed. He had the wonderful quality many academics have--which is that he was interested in the kinds of questions that all of us care about but never have the time or opportunity to explore. He had also had a quality that is rare among academics. He had the ability to translate his work for people who were outside his world.

Now Gilbert has written a book about his psychological research. It is called Stumbling on Happiness, and reading it reminded me of that plane ride long ago. It is a delight to read. Gilbert is charming and funny and has a rare gift for making very complicated ideas come alive.

Stumbling on Happiness is a book about a very simple but powerful idea. What distinguishes us as human beings from other animals is our ability to predict the future--or rather, our interest in predicting the future. We spend a great deal of our waking life imagining what it would be like to be this way or that way, or to do this or that, or taste or buy or experience some state or feeling or thing. We do that for good reasons: it is what allows us to shape our life. And it is by trying to exert some control over our futures that we attempt to be happy. But by any objective measure, we are really bad at that predictive function. We're terrible at knowing how we will feel a day or a month or year from now, and even worse at knowing what will and will not bring us that cherished happiness. Gilbert sets out to figure what that's so: why we are so terrible at something that would seem to be so extraordinarily important?

In making his case, Gilbert walks us through a series of fascinating--and in some ways troubling--facts about the way our minds work. In particular, Gilbert is interested in delineating the shortcomings of imagination. We're far too accepting of the conclusions of our imaginations. Our imaginations aren't particularly imaginative. Our imaginations are really bad at telling us how we will think when the future finally comes. And our personal experiences aren't nearly as good at correcting these errors as we might think.

I suppose that I really should go on at this point, and talk in more detail about what Gilbert means by that--and how his argument unfolds. But I feel like that might ruin the experience of reading Stumbling on Happiness. This is a psychological detective story about one of the great mysteries of our lives. If you have even the slightest curiosity about the human condition, you ought to read it. Trust me. --Malcolm Gladwell