 Since the 1960s, philosophers of biology have questioned the existence of biological laws of nature. J. J. C. Smart (1963) emphasized the earth-boundedness of the biological sciences (in conflict with the universality of natural laws). No purported “law” in biology has been found to be exceptionless, even for life on earth (in conflict with the generality of laws). And John Beatty (1995) argued that the purported “laws” of, for example, Mendelian genetics, were contingent on evolution (in conflict with the necessity of natural laws). (For further discussion, see Brandon 1997; Lange 2000; Mitchell 1997; Sober 1997; Waters 1998; Weber 2005.) Hence, philosophers’ search for biological laws of nature, characterized as universal, necessary generalizations, has ceased.