Common sense … has the very curious property of being more correct retrospectively than prospectively. It seems to me that one of the principal criteria to be applied to successful science is that its results are almost always obvious retrospectively; unfortunately, they seldom are prospectively. Common sense provides a kind of ultimate validation after science has completed its work; it seldom anticipates what science is going to discover.

The most valuable and least replacable resource is time.

It is far better to do the right thing wrong than to do the wrong thing right.

Every problem interacts with other problems and is therefore part of a set of interrelated problems, a system of problems. I choose to call such a system a mess.

Creativity is the ability to identify self-imposed constraints, remove them, and explore the consequences of their removal.

A bureaucrat is one who has the power to say "no" but none to say "yes."

Managers are not confronted with problems that are independent of each other, but with dynamic situations that consist of complex systems of changing problems that interact with each other. I call such situations messes. Problems are extracted from messes by analysis. Managers do not solve problems, they manage messes.