There are two ways of constructing a software design: One way is to make it so simple that there are obviously no deficiencies, and the other way is to make it so complicated that there are no obvious deficiencies. The first method is far more difficult.

I call it my billion-dollar mistake. It was the invention of the null reference in 1965.

I couldn't resist the temptation to put in a null reference, simply because it was so easy to implement. This has led to innumerable errors, vulnerabilities, and system crashes, which have probably caused a billion dollars of pain and damage in the last forty years.

Premature optimization is the root of all evil in programming.

Inside every large program is a small program struggling to get out.

The job of formal methods is to elucidate the assumptions upon which formal correctness depends.

The real value of tests is not that they detect bugs in the code but that they detect inadequacies in the methods, concentration, and skills of those who design and produce the code.