In this essay, James Murphy gives a brief history of the concept of legal positivism. The term “positivism” has its origins in the quasi-religious philosophy promoted by the 19th-century Frenchman, Auguste Comte. Legal positivism and Comtean positivism are very different, but they have in common a rejection of moral and physical arguments in favor of arguments based in empirical fact. Legal positivism has two main theses: 1) that law can always be traced to objective acts of legislation or judging, and 2) that law has no necessary connection to natural law or to any ethical principle. Recently, however, some scholars have criticized the notion of legal positivism; arguing that natural law theories allow for positive law, and that many legal positivists make arguments that are implicitly based on a concept of natural law.