The tools we use have a profound and devious influence on our thinking habits, and therefore on our thinking abilities.

Computer science is no more about computers than astronomy is about telescopes, biology is about microscopes or chemistry is about beakers and test tubes. Science is not about tools. It is about how we use them, and what we find out when we do.

Computer science has as much to do with computers as astronomy has to do with telescopes.

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.

If we wish to count lines of code, we should not regard them as "lines produced" but as "lines spent."

The use of COBOL cripples the mind; its teaching should, therefore, be regarded as a criminal offense.

Experience does by no means automatically leads to wisdom and understanding.