Many of us recognize the serious ethical problems confronting us, and want to change the world towards the better. So why do so few of us go on to do so, even when we are convinced that we should? At least since Plato philosophers have argued over the power of reason to bring about change. But abstract reason on its own, it turns out, is unable to motivate us. Simply knowing what the right thing to do is, isn’t enough. It’s only when our emotions, when our empathy, become engaged that we feel the pull of our reasoning, argues Lori Gruen.