The adage has been attributed to a number of sources. It appeared in print on page six of The Washington Post dated October 25, 1911, in the form: "Nor would a wise man, seeing that he was in a hole, go to work and blindly dig it deeper... '' In The Bankers Magazine, it was published in 1964 as: "Let me tell you about the law of holes: If you find yourself in a hole, stop digging. ''
who said if you find yourself in a hole stop digging
The Washington Post