Famous quotes by EwDijkstra: ---- '''On programming''': "Always design your programs as a member of a whole family of programs, including those that are likely to succeed it." "Separate Concerns" "A Programming Language is a tool that has profound influence on our thinking habits." "The use of COBOL cripples the mind; its teaching should, therefore, be regarded as a criminal offense." "The competent programmer is fully aware of the strictly limited size of his own skull; therefore he approaches the programming task in full humility, and among other things he avoids clever tricks like the plague." [EWD340] "Program testing can best show the presence of errors but never their absence." "Don't set a flag; set the data." "It is practically impossible to teach good programming to students that have had a prior exposure to BASIC: as potential programmers, they are mentally mutilated beyond hope of regeneration." ---- '''On ComputingScience in general, and methodology in particular''': "Progress is possible only if we train ourselves to think about programs without thinking of them as pieces of executable code." "Object-oriented programming is an exceptionally bad idea which could only have originated in California." ** ''It originated in Norway! -- AnonymousDonor'' ** But California wants to ''be'' Norway, especially after Bush was re-elected. "I mean, if 10 years from now, when you are doing something quick and dirty, you suddenly visualize that I am looking over your shoulders and say to yourself, "Dijkstra would not have liked this", well that would be enough immortality for me." "Automatic computers have now been with us for a quarter of a century. They have had a great impact on our society in their capacity of tools, but in that capacity their influence will be but a ripple on the surface of our culture, compared with the much more profound influence they will have in their capacity of intellectual challenge without precedent in the cultural history of mankind." [EWD340] "The Fathers of the field had been pretty confusing: John von Neumann speculated about computers and the human brain in analogies sufficiently wild to be worthy of a medieval thinker and Alan M. Turing thought about criteria to settle the question of whether Machines Can Think, a question of which we now know that it is about as relevant as the question of whether Submarines Can Swim." [EWD898] "Computer Science is no more about computers than astronomy is about telescopes." *Am I the only one who thinks this has little value as a thought? How about cakes and cake pans? Shovels to ditches? There doesn't seem to be a point. **You see?! You see what happens when they stop teaching theory and keep calling it "Computer Science"!!! **Sure there is. Computers are a tool and an inspiration, but they aren't the real subject matter of Computer Science as practiced by EwDijkstra. **Note: Leonhard Euler never touched a computer, yet is held in the same regards as EwDijkstra. "A formula is worth a thousand pictures." ---- '''On CriticalSpirit, intellectual hygiene and more general cultural issues''': "Being abstract is something profoundly different from being vague … The purpose of abstraction is not to be vague, but to create a new semantic level in which one can be absolutely precise." "As a matter of fact the still often repeated requirement that axioms should be "self evident" strikes me as a medieval relic: to the extent that they take philosophy seriously, it is impossible to me to take logicians seriously. (Again this may be a cultural difference: it seems there are societies in which philosophers still have some intellectual standing.)" * ''Eh? If it's not self evident, then you have to have grounds for holding to it. If its truth is dependent on prior grounds, then it's not an axiom.'' "...the distinction between "what one says" and "how one says it" is ultimately untenable." [EWD683] ---- '''Said about Dijkstra''': Arrogance in computer science is measured in nano-Dijkstraas -- Alan Kay ---- ---- Sources: * http://en.wikiquote.org/wiki/Edsger_W._Dijkstra * http://www.brainyquote.com/quotes/authors/e/edsger_dijkstra.html * http://www.quotationspage.com/quotes/E._W._Dijkstra/ * http://www.goodreads.com/author/quotes/1013817.Edsger_W_Dijkstra * http://www.cs.scranton.edu/~mccloske/dijkstra_quotes.html For criticism of some his statements, see DijkstraIsntGod.