In the years of the post-Darwinian debate, many American naturalists invoked the name of Lamarck to signal their belief in a purposive and anti-Darwinian view of evolution. Yet Weismann’s theory of germ-plasm continuity undermined the shared tenet of the neo-Lamarckian theories as well as the idea of the interchangeability between biological and social heredity. Edward Drinker Cope, the leader of the so-called “American School,” defended his neo-Lamarckian philosophy against every attempt to redefine the relationship between behavior, development, and heredity beyond (...) the epigenetic model of inheritance. This paper explores Cope’s late-career defense of neo-Lamarckism. Particular attention is dedicated to the debate he had with James Mark Baldwin before the publication of Baldwin’s own “A New Factor in Evolution”. I argue that Cope’s criticism was partly due to the fact that Baldwin’s theory of social heredity threatened Cope’s biologistic stance, as well as his attempt to preserve design in nature. This theoretical attitude had a remarkable impact on Baldwin’s arguments for the theory of organic selection. (shrink)

Scholars have often considered evolutionary social theories a product of Positivist scientism and the naturalization of ethics. Yet the theistic foundations of many evolutionary theories proposed between the nineteenth and the twentieth centuries bolstered the belief that following natural laws was morally desirable, if not vital, to guaranteeing social and moral progress. In the early twentieth century, American paleontologist and leading evolutionist Henry Fairfield Osborn represented one of the most authoritative advocates of this interpretation of natural normativity. Particularly during the (...) last years of his career, Osborn used theological arguments to reinforce his advocacy of evolutionary ethics and social control policies, which led him to challenge his “old master” Thomas Huxley regarding the separation between evolution and moral conduct. This article examines the development of Osborn’s evolutionary ethics, with particular regard to its bearing on the American debate on euthenics. I argue that theistic topics played a major rhetorical role in the attempt to justify normative conclusions drawn from ostensible laws of evolution. (shrink)