There are two kinds of math: the hard kind and the easy kind. The easy kind, practiced by ants, shrimp, Welsh Corgis — and us — is innate. But what innate calculating skills do we humans have? Leaving aside built-in mathematics, such as the visual system, ordinary people do just fine when faced with mathematical tasks in the course of the day. Yet when they are confronted with the same tasks presented as "math," their accuracy often drops. If we have innate mathematical ability, why do we have to teach math and why do most of us find it so hard to learn? Are there tricks or strategies that the ordinary person can do to improve mathematical ability? Can we improve our math skills by learning from dogs, cats, and other creatures that "do math?" The answer to each of these questions is a qualified yes. All these examples of animal math suggest that if we want to do better in the formal kind of math, we should see how it arises from natural mathematics.

基思.德夫林(Keith Devlin,1947--)是斯坦福大学语言与信息研究中心行政主任和斯坦福大学数学系的顾问教授,美国科学院数学科学教育委员会委员,世界经济论坛成员,美国科学促进会成员,美国全国公共电台数学普及节目主持人.他是24本书、一张互动式CD光盘和75篇已发表的研究论文的作者，以“数学小子”而著称。其著作有：《千年难题》、《数学犹聊天》、《数学化生命》等。