As a child Ludwig Wittgenstein received formal instruction in Roman Catholicism. Later on, conversations with his sister Gretl destroyed his childish faith. He became indifferent to, perhaps even contemptuous of, religious belief. When he was about 21 years of age, however, something occurred that had a lasting impact on him. He saw a play in Vienna which was mediocre drama: but there was a scene in which a person whose life had been desperately miserable, and who thought himself about to die, suddenly felt himself to be spoken to in the words, ‘Nothing can happen to you!’ No matter what occurred in the world, no harm could come to him! Wittgenstein was greatly struck by this thought (as he told me approximately forty years later): for the first time he perceived the possibility of religious belief (NM, p. 58).