Jean-Paul Lévy's book is marked by a resolutely materialistic reflexion, characteristic of biologists : the only thing that distinguishes man from all other living things is the capacity to reason. From this prospective, he explains how a human body is constructed, how and why it produces thoughts and why, one day, it finally ceases to function and dies. His thought process leads to a materialistic solution of the problem of the union of the body and soul.

Jean-Paul Lévy is a hematologist and immunologist. He heads France's National Agency for AIDS Research