In his autobiography, published posthumously in 1960, Richard Goldschmidt wrote: “I am confident that in twenty years my [work], which is now ignored, will be given an honorable place in the history of evolutionary thought.” The publication of this edition, now reissued with a new introduction by Stephen Jay Gould, proves Goldschmidt’s prediction to be correct. Goldschmidt, one of the world’s great geneticists, delivered the prestigious Silliman lectures at Yale University in 1939 and published his remarks in 1940 as The Material Basis of Evolution. His intent was to inquire into the types of hereditary differences that produce new species. Goldschmidt used a wide range of research to formulate his own picture of evolution. Contrary to most scientists, he insisted that the neo-Darwinist theory of micromutations was no longer tenable as a general theory of evolution. Instead, Goldschmidt claimed, macroevolution accounted for the larger steps in evolution. Although Goldschmidt’s views were reviled by scientists of his day, some of his basic ideas are now gaining acceptance. As Gould writes in his introduction: “I do…believe that its general vision is uncannily correct (or at least highly fruitful at the moment) in several important areas where conventional Darwinian theory has become both hidebound and unproductive.”