The supernatural is being swept out of the universe in the flood of new knowledge of what is natural. It will soon be as impossible for an intelligent, educated man or woman to believe in a god as it is now to believe the earth is flat, that flies can be spontaneously generated... or that death is always due to witchcraft... The god hypothesis is no longer of any pragmatic value for the interpretation or comprehension of nature, and indeed often stands in the way of better and truer interpretation. Operationally, God is beginning to resemble not a ruler but the last fading smile of a cosmic Cheshire cat.

Religion without Revelation (1957) p. 58