Can biology define life? "[An] ingenious mixture of science and philosophy. . . . highly thought-provoking." — Kirkus Reviews (starred review)

In this book a professor, biologist, and physiologist argues that modern Darwinism's materialist and mechanistic biases have led to a scientific dead end, unable to define what life is—and only an openness to the qualities of purpose and desire will move the field forward.

As Scott Turner contends: "To be scientists, we force ourselves into a Hobson's choice on the matter: accept intentionality and purposefulness as real attributes of life, which disqualifies you as a scientist; or become a scientist and dismiss life's distinctive quality from your thinking. I have come to believe that this choice actually stands in the way of our having a fully coherent theory of life."

Growing research shows that life's most distinctive quality, shared by all living things, is purpose and desire: maintain homeostasis to sustain life. In Purpose and Desire, Turner draws on the work of Claude Bernard, a contemporary of Darwin revered among physiologists as the founder of experimental medicine, to build on Bernard's "dangerous idea" of vitalism, which seeks to identify what makes "life" a unique phenomenon of nature. To further its quest to achieve a fuller understanding of life, Turner says, science must move beyond strictly accepted measures that consider only the mechanics of nature. A thoughtful appeal to widen our perspective of biology that is grounded in scientific evidence, Purpose and Desire helps us bridge the ideological evolutionary divide.

"A must-read for everybody interested in the science of life and evolution . . . one of those rare science books which inquisitive laypeople will equally enjoy. Purpose and Desire will change the way you think of life." — Washington Book Review

"[A] beautifully written book, brimming with anecdotes and biological insights . . . will leave readers moved by Turner's deep appreciation of life's exquisiteness, its richness, and diversity . . . a provocative thesis, but one that is a wonderfully rich read, thought-provoking, and highly recommended." — The Quarterly Review of Biology