 “Positivism” is a term introduced by Auguste Comte (1798–1857), a French philosopher who championed the natural and social sciences over against theology and the philosophical practice of metaphysics. The term “positivism” was used later (sometimes amplified to Logical Positivism by A.J. Ayer) by a group of philosophers who met in Austria called the Vienna Circle from 1922 to 1938. This group, which included Moritz Schlick and Max Planck, advanced an empirical account of meaning, according to which for a proposition to be meaningful it needed either to be a conceptual or formal statement in mathematics or about analytic definitions (“triangles have three angles”) or about matters that can be empirically verified or falsified. Ostensibly factual claims that do not make any difference in terms of our actual (or possible) empirical experience are void of meaning. A British philosopher, who visited the Vienna Circle, A.J. Ayer popularized this criterion of meaning in his 1936 book, Language, Truth, and Logic. In it, Ayer argued that religious claims as well as their denial were without cognitive content. By his lights, theism, and also atheism and agnosticism, were nonsense, because they were about the reality (or unreality or unknowability) of that which made no difference to our empirical experience. How might one empirically confirm or disconfirm that there is an incorporeal, invisible God or that Krishna is an avatar of Vishnu? Famously, Antony Flew employed this strategy in his likening the God of theism to a belief that there is an undetectable, invisible gardener who could not be heard or smelled or otherwise empirically discovered (Flew 1955). In addition to rejecting traditional religious beliefs as meaningless, Ayer and other logical positivists rejected the meaningfulness of moral statements. By their lights, moral or ethical statements were expressions of persons’ feelings, not about values that have a reality independent of persons’ feelings.