We all strive to think rationally. But it doesn’t always do us much good. Cutting-edge science has revealed that if we want to sharpen our thinking, we need to feel our feelings. That science is the subject of “Emotional,” a new book by theoretical physicist Leonard Mlodinow. In this episode, he sits down with science writer Annie Murphy Paul to discuss where emotions come from, how they motivate us, and what we can do to control them.