In the software business there are many enterprises for which it is not clear that science can help them; that science should try is not clear either.

In the good old days physicists repeated each other's experiments, just to be sure. Today they stick to FORTRAN, so that they can share each other's programs, bugs included.

The art of programming is the art of organizing complexity.

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.

Elegance is not a dispensable luxury but a factor that decides between success and failure.

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

A most important, but also most elusive, aspect of any tool is its influence on the habits of those who train themselves in its use. If the tool is a programming language this influence is, whether we like it or not, an influence on our thinking habits.... A programming language is a tool that has profound influence on our thinking habits.