Edsger W. Dijkstra quotes
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Edsger W. Dijkstra quotes
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Various interesting quotes from computer scientist Edsger Wybe Dijkstra (1930 - 2002).


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(EWD 936 - On anthropomorphism in science)
But the blur continues to linger on, and has a much wider impact than you might suspect. You see, it is not only that the question “Can machines think?” is regularly raised; we can —and should— deal with that by pointing out that it is just as relevant as the equally burning question “Can submarines swim?” A more serious byproduct of the tendency to talk about machines in anthropomorphic terms is the companion phenomenon of talking about people in mechanistic terminology. The critical reading of articles about computer-assisted learning —excuse me: CAL for the intimi— leaves you no option: in the eyes of their authors, the educational process is simply reduced to a caricature, something like the building up of conditional reflexes. For those educationists, Pavlov’s dog adequately captures the essence of Mankind —while I can assure you, from intimate observations, that it only captures a minute fraction of what is involved in being a dog—.
November 12, 2025 at 5:41 PM
ewdquotes.bsky.social
(EWD 1284 - Computing Science: Achievements and Challenges )
A major milestone of ALGOL 60 was its introduction of recursion into imperative programming. Aside Its inclusion was almost an accident and certainly a coup. When the ALGOL 60 Report was nearing completion and circulated for final comments, it was discovered that recursion was nowhere explicitly excluded, and, just to be sure that it would be in, one innocent sentence was added at the end of the Section 5.4.4., viz. “Any other occurrence of the procedure identifier within the procedure body denotes activation of the procedure.”. Some committee members only noticed this sentence when it was too late to oppose, got very cross and refused to implement it. In more than one sense they were the losers. (End of aside)
November 12, 2025 at 5:08 PM
ewdquotes.bsky.social
EWD 1165
In my experience —gathered on different continents—, it is impossible to completely prevent all snake oil peddling on campus, but by openly despising it one can at least save the integrity of the academic enterprise as a whole.
November 12, 2025 at 12:18 PM
ewdquotes.bsky.social
About the birth of "Dijkstra's algorithm"

(EWD 1166)
I designed my first nontrivial algorithms. The algorithm for The Shortest Path was designed for the purpose of demonstrating the power of the ARMAC at its official inauguration in 1956, the one for The Shortest Spanning Tree was designed to minimize the amount of copper in the backpanel wiring of the X1. In retrospect, it is revealing that I did not rush to publish these two algorithms: at that time, discrete algorithms had not yet acquired mathematical respectability, and there were no suitable journals. Eventually they were offered in 1959 to "Numerische Mathematik" in an effort of helping that new journal to establish itself. For many years, and in wide circles, The Shortest Path has been the main pillar for my name and fame, and then it is a strange thought that it was designed without pencil and paper, while I had a cup of coffee with my wife on a sunny cafe terrace in Amsterdam, only designed for a demo....
November 12, 2025 at 12:04 PM
ewdquotes.bsky.social
(EWD 952)
Usually I don't need to talk about artificial intelligence as it is only a specific area of potential machine application and as such outside the scope of computing science proper. I have to do it, however, as soon as it is proposed that, by applying AI techniques, machines will solve the software problems we don't know how to solve ourselves. Our first reaction to the Fifth Generation Project was a sigh of relief, in the style of "Well, if the Japanese industry tries to cash in on AI, that will take care of the Japanese competition.". Within a week or so came the sad realization that the Western world would probably lack the backbone needed for not joining that bandwagon.
November 12, 2025 at 11:55 AM
ewdquotes.bsky.social
(EWD 1305)
And I don't need to waste my time with a computer just because I am a computer scientist. [Medical researchers are not required to suffer from the diseases they investigate.]
November 12, 2025 at 11:15 AM