The purpose of abstraction is not to be vague, but to create a new semantic level in which one can be absolutely precise.

There is very little point in trying to urge the world to mend its ways as long as that world is still convinced that its ways are perfectly adequate.

APL is a mistake, carried through to perfection.

It is a mistake to think that programmers wares are programs. Programmers have to produce trustworthy solutions and present it in the form of cogent arguments. Programs source code is just the accompanying material to which these arguments are to be applied to.

About the use of language: it is impossible to sharpen a pencil with a blunt axe. It is equally vain to try to do it with ten blunt axes instead.

In passing I draw attention to another English expression which often occurs in Dutch texts: "the real world". In Dutch - and I am afraid not in Dutch alone - its usage is almost always a symptom of a violent anti-intellectualism.

Thanks to the greatly improved possibility of communication, we overrate its importance. Even stronger, we underrate the importance of isolation.