Recently, I was invited to give a grand rounds lecture at a mental facility in Princeton, New Jersey. I arrived early and had a chance to walk the grounds. Everywhere, I encountered notices that thanked me for not smoking.

What is wrong with this picture?

Eighty percent of individuals with schizophrenia and some two-thirds of us with bipolar smoke. The habit undoubtedly contributes to our appallingly shorter life-spans than the general population. But clearly, a lot more is going on than a simple...