The maxim itself is an example of itself. If you go to the archives of newspapers you might think the maxim “turns up in the historical record in” 2002. But if you do a bit of research you see that Carl Sagan, who most often gets the credit for the maxim in scientific circles, used those words in 1995 in The Demon-Haunted World. But history goes back more than that. He seems to have originated the phrase. In 1972, Richard Berendzen, the chairman of a conference of scientists, including Sagan, meeting to discuss the possibility of life elsewhere in the universe, attributed the maxim to the great British cosmologist Martin Rees. Actually, the English writer William Cowper (1731-1800) had written something very similar. He wrote the “Absence of proof is not proof of absence.” Close enough.