Software development is technical activity conducted by human beings.

Complexity has and will maintain a strong fascination for many people. It is true that we live in a complex world and strive to solve inherently complex problems, which often do require complex mechanisms. However, this should not diminish our desire for elegant solutions, which convince by their clarity and effectiveness. Simple, elegant solutions are more effective, but they are harder to find than complex ones, and they require more time, which we too often believe to be unaffordable

It is evidently necessary to generate and test candidates for solutions in some systematic manner.

I am convinced that there is a need for high quality software, and the time will come when it will be recognized that it is worth investing effort in its development and in using a careful, structured approach based on safe, structured languages.

Software is getting slower more rapidly than hardware becomes faster.

During the process of stepwise refinement, a notation which is natural to the problem in hand should be used as long as possible.

Program construction consists of a sequence of refinement steps.