 The adequacy of evolutionary ethical naturalism as a foundation for ethical realism has been a point of contention for Darwin’s contemporaries and successors since the publication of the Descent. For some moral philosophers, Darwin had simply reduced ethics to a property subject to the relativizing tendencies of natural selection (Farber 1994: chp. 5). It was, in the view of Darwin’s philosophical critics, to reduce ethics to biology and in doing so, to offer no way to distinguish ethical goods from survival advantages. Not even for some strong supporters of Darwinism, such as Thomas Huxley and Alfred Russel Wallace, was Darwin’s account adequate (Farber 1994: chp. 4). Much of subsequent moral philosophy was to be grounded upon the canonical acceptance of the “is-ought” distinction,  which developed from this critique of “evolutionary” ethical theory. Receiving its most influential expression in G. E. Moore ’s (1873–1958) Principia Ethica (1903)—itself an attack on Spencer’s version of evolutionary ethics—, the debate over the adequacy of evolutionary ethics has continued (Hauser 2006; Katz (ed.) 2000; Maienschein &amp; Ruse (eds.) 1999).