Life By the Numbers

Why do leopards grow spots when tigers grow stripes? Is the universe round, square, or some other shape? How do the dimples in a golf ball give it greater lift? Is there such a thing as a public mood? If so, how can we accurately take its pulse?

Only one tool of the human mind has the power and versatility to answer so many questions about our world—mathematics. Far from a musty set of equations an...