"The only way for errors to occur in a program is by being put there by the author. No other mechanisms are known. Programs can't acquire bugs by sitting around with other buggy programs. Right practice aims at preventing insertion of errors and, failing that, removing them before testing or any other running of the program."

Previous Quote

I can only think that the book is read because it deals with the difficulties of schooling, which do not change. Please note: the difficulties, not the problems. Problems are solved or disappear with the revolving times. Difficulities remain. It will always be difficult to teach well, to learn accurately; to read, write, and count readily and competently; to acquire a sense of history and start one's education or anothers.

— Jacques Barzun