To Err is Human; To Really Foul Things Up Requires a Computer

Paul Ehrlich? Alexander Pope? Senator Soaper? Bill Vaughan? Agatha Christie? Anonymous?

Dear Quote Investigator: I am reading your blog and that shows I am not a Luddite, but computers can be very exasperating. One of my favorite quotations on this topic is the following:

To err is human, but to really foul things up you need a computer.

When I tried to find out who said this originally I came across the name of biologist Paul Ehrlich. He wrote an influential and controversial book “The Population Bomb” in 1968. But I cannot figure out where or when Ehrlich said this quotation. Would you delve into this and determine the specifics? I suspect that it is another anonymously authored witty remark.

Quote Investigator: The popularity of this funny maxim is indicated by its appearance in the Oxford Dictionary of Quotations, 1 the Yale Book of Quotations, 2 and the Columbia Dictionary of Quotations. 3 In each of these three references the adage is presented as anonymous. The Yale Book of Quotations gives the earliest cite dated October 3, 1969.

Paul Ehrlich is credited with the quote in some places, e.g., in a listing of “101 Great Computer Programming Quotes”. 4 But the earliest examples of the phrase attributed to Ehrlich were published many years after the words originally appeared in print.

In 1969 a thematically similar remark appeared in the book “Hallowe’en Party” by the famous mystery writer Agatha Christie: 5

I know there’s a proverb which says, ‘To err is human’ but a human error is nothing to what a computer can do if it tries.”

A separate article about the Christie quotation is available here.

The first close match located by QI appeared on April 2, 1969 and was credited to a comical personage named ‘Senator Soaper’ who was the fictional alter ego of the newspaper columnist Bill Vaughan. The words initially appeared under that name in a Virginia paper: 6

To err is human, to really foul things up requires a computer.

Current evidence suggests that William E. Vaughan crafted this phrase although it is possible he was influenced by the Agatha Christie passage.
Continue reading To Err is Human; To Really Foul Things Up Requires a Computer


  1. Oxford Dictionary of Quotations edited by Elizabeth Knowles, “Sayings 49”, Oxford Reference Online, Oxford University Press. (Accessed 2010 October 6)
  2. 2006, The Yale Book of Quotations by Fred R. Shapiro, Page 670, Yale University Press, New Haven. (Verified on paper)
  3. 1993, The Columbia Dictionary of Quotations [Inside title Columbia Book of Quotations], Page 171, Columbia University Press, New York. (Google Books preview) link
  4. 2008 January 1, Website:, DevTopics: Software Development Topics, 101 Great Computer Programming Quotes. (Accessed December 5, 2010) link
  5. 1970 (Copyright 1969), Hallowe’en Party by Agatha Christie, Quote Page 35, Pocket Books, New York. (First published in 1969; this is 1970 paperback edition) (Verified with scans)
  6. 1969 April 2, Free Lance-Star, Senator Soaper [Free standing quote], Page 1, Column 2, Fredericksburg, Virginia. (Google News archive)