"Can reading a book make you more rational? Can it explain why there seems to be so much irrationality in the world, including, let's be honest, in each of us? These are the goals of Steven Pinker's follow-up to Enlightenment Now (Bill Gates's "new favorite book of all time"). Humans today are often portrayed as cavemen out of time, poised to react to a lion in the grass with a suite of biases, blind spots, fallacies, and illusions. But this, Pinker...