Jan L. A. van de Snepscheut Quotes

Johannes Lambertus Adriana van de Snepscheut was a computer scientist and educator. He was a student of Martin Rem and Edsger Dijkstra. At the time of his death he was the executive officer of the computer science department at the California Institute of Technology. He was also developing an editor for proving theorems called "Proxac".In the early morning hours of February 23, 1994, van de Snepscheut attacked his sleeping wife, Terre, with an axe. He then set their house on fire, and died as it burned around him. Terre and their three children escaped their burning home. Wikipedia

✵ 12. September 1953 – 23. February 1994

“In theory, there is no difference between theory and practice. But, in practice, there is.”

Jan L. A. van de Snepscheut

The earliest known appearance in print of this quote is Benjamin Brewster in the October 1881 - June 1882 issue of "The Yale Literary Magazine." Brewster asks, "What does his lucid explanation amount to but this, that in theory there is no difference between theory and practice, while in practice there is?" See page 202. https://books.google.com/books?id=iJ9MAAAAMAAJ&printsec=frontcover&vq=%22no+difference%22#v=onepage&q&f=false It has also been attributed by Doug Rosenberg and Matt Stephens (2007) Use Case Driven Object Modeling with UMLTheory and Practice p. xxvii as well as Walter J. Savitch, Pascal: An Introduction to the Art and Science of Programming (1984), where it is attributed as a "remark overheard at a computer science conference". It circulated as an anonymous saying for more than ten years before attributions to van de Snepscheut and Yogi Berra began to appear (and later still to various others).
Misattributed