At some profound level, Michael had discovered, extremely depressed people have become disconnected from a sense of the future, in a way that other really distressed people have not. From this early research, though, it was hard to tell if these kids’ symptoms were a cause or an effect. It could go either way. Maybe losing a sense of the future makes you suicidal—or maybe being extremely depressed makes it hard to think about the future. How, he wondered, could he figure this out?

