Confused about depression? Depressed about your confusion? Tired of interminable arguments about whether antidepressants are the spawn of the Devil or Manna from Heaven? Well, so am I. So I decided to do something about it. I wrote a book about how we got to the point where it even makes sense to think of our unhappiness as a disease. The book took me on a long expedition—to clinical trials, doctors' offices, therapy training seminars, and libraries full of dusty old history books. I got interviewed and medicated and even had my brain scanned by a doctor named Amen, and no I did not make that up.

I returned a little less confused, but sure of at least one thing. Depression is not the disease that the doctors and drug companies want you to think it is. That biochemical imbalance they tell you about when they explain why your unhappiness is an illness like diabetes? They're not really sure such a thing exists. In fact, when they talk to each other, they say that one of the things they know is that depression, even the severe kind, is not a simple imbalance of chemicals.

Which doesn't mean depression isn't a problem, and that brain chemicals aren't part of the problem, or that you shouldn't take drugs that make you feel better. It just means that the story is more complicated (and interesting) than the one about depression being a disease like diabetes. That bigger story is the one I tell in my book. It starts in 5000 BC with the Book of Job, the one about the poor fellow who was the butt of a joke Satan played on God. It ends last year. In between, I write about purple dyes, syphilis, and mercury underpants, as well as subjects you'd expect like psychoanalysis and shock therapy. I recount various pranks that have been played by people like Mark Twain on doctors who have grown too big for the britches, including Sigmund Freud. I retrieve from the dustbin of history a couple of important bicycle rides, taken under the influence of powerful drugs, which were crucial to the development of antidepressants. I tell you why Prozac is a lot more like LSD, chemically and culturally, than anyone wants to admit, how psychiatrists destroyed their profession in order to save it, and in the bargain defined mental illness without consideration of the actual conditions under which we live our lives. I take no prisoners, and I have a lot of fun doing it. You'll have a good time reading it, too, I guarantee. The World Health Organization says that depression is soon to be the leading cause of disability in the world, so it's very likely you'll encounter the diagnosis one way or the other. And if you read this book, you will be better equipped to understand what it means and what you might want to do about it.