What Is an Explanation?

Making Sense of Life Explaining Biological Development with Models, Metaphors, and Machines. Evelyn Fox Keller. Harvard University Press, Cambridge, MA, 2002. 400 pp. $29.95, £20.50, $29.95. ISBN 0-674-00746-8. Motivated by the philosophical problem of what it means to understand organismal development, Keller offers a selective history of developmental biology with a focus on the contributions of mathematical and theoretical approaches.