W.D. Hamilton (1936-2000) was one of the most influential evolutionary biologists of the 20th century. He is best known as the originator of Inclusive Fitness Theory, which at the time was regarded as a breakthrough solution to the evolution of altruism compared to the failed theory of group selection.

Less well known is that Hamilton changed his mind about the relationship between his theory and group selection, based on the work of another theoretical biologist named George Price. The fact that this is still news to many people is curious, since Hamilton himself wrote about it over 40 years ago[1], Elliott Sober and I called attention to it in our book Unto Others over 20 years ago, and the historian of science Oren Harman wrote about it in his best-selling book The Price of Altruism almost ten years ago.

In my interview with Harman, we tell the story of Hamilton’s conversion one more time and then tackle the fascinating question of why it remains news to so many people after all these years.

This is the second of a series of interviews designed to achieve a long overdue consensus on Multilevel Selection Theory. The first interview, with Elliott Sober, is titled “Was Darwin a Group Selectionist?”.



[1] Hamilton, W. D. (1975). Innate social aptitudes in man, an approach from evolutionary genetics. In R. Fox (Ed.), Biosocial anthropology (pp. 133–155). London: Malaby Press.