Abstract

According to C. S. Lewis, Naturalism is beset by a “cardinal difficulty.” It can be known to be true only by way of valid reasoning—something precluded by Naturalism itself. The Naturalist’s belief in Naturalism hasn’t been caused by a rational argument; it has resulted instead from irrational causes. In the face of Elizabeth Anscombe’s powerful and searching criticisms, Lewis significantly revised his argument against Naturalism for the 1960 edition of his book Miracles. Anscombe’s last words on Lewis’ argument were delivered at a meeting of the Oxford C. S. Lewis Society, November 12, 1985. The rewritten argument, she contends, is “genuinely problematic.” First, it fails to answer a question Lewis says it must: what is the connection between the logical grounds of a belief and its actual occurrence? Secondly, it invokes the “damnably obscure proposition ‘knowledge determined only by the truth it knows’”—a proposition “obviously crucial” to Lewis’ case, but which he sadly “doesn’t explore.” I argue that Anscombe last words here are mistaken on both counts.