Where does our mathematical ability come from? Our prehistoric ancestors' brains were essentially the same as ours, so they must have had the same underlying ability. What purpose could it serve in 50,000 BC? And what exactly goes on in our brains when we multiply 15 by 36 or prove Fermat's Last Theorem? The answer, according to Keith Devlin, is closely related to the evolutionary changes in the human brain that gave rise to language. It lies within our genes and more specifically with the pattern-making abilities with which we are born. Devlin uses these insights to show why some people loathe mathematics, why others find it so difficult, and why a select few excel at the subject. He also suggests ways in which we can improve our mathematical skills.