of organic evolution from the noted biologist and scientific popularizer. Dr. Simpson credits himself with a highfalutin' motive- ""Being the process by which we ourselves came to be"", the understanding of evolution is ""crucial for comprehension of our place in and relationship to the objective world"", thereby illuminating in turn the subjective. But the book's rather randomly-connected essays, most of which have been previously published and concern certain historical, philosophical and technical aspects of Darwinism and genetics, are no match for- at least in the matter of sustaining interest- one of his previous efforts, the striking Meaning of Evolution. There are, however, rewards: a funny summary of Samuel Butler's anti-Darwin trickery; a challenging encounter what is here considered the contemporary failure of nerve and logic in Teil de Chardin's ""evolutionary mystique""; well-balanced expositions of the findings of Dobzhansky and Mayr, the speculations of Bridgman, Pearson and Russell; demolition of Lamarckian adaptation; and a debunking probe into the possibilities of extraterrestrial life. Though things go slack now and then, Dr. Simpson's style anyway- is uncommonly good: personalized, exuberant, enlightening.