Nothing is harder to topple than a fact that supports a deeply held prejudice denied by its holder.

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.

Managers who don't know how to measure what they want settle for wanting what they can measure.

So much time is currently spent in worrying about the future that the present is allowed to go to hell.

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.

No problem stays solved in a dynamic environment.