The same thinking and actions that created our problems cannot be used to solve them.

We must dedicate our lives to drying up the source of war: ammunition factories.

Knowledge is realizing that the street is one way; wisdom is looking in both directions anyway.

Manager solves problems, leader prevents them.

I would not think that philosophy and reason themselves will be man's guide in the foreseeable future; however, they will remain the most beautiful sanctuary they have always been for the select few.

Considered logically this concept is not identical with the totality of sense impressions referred to; but it is an arbitrary creation of the human (or animal) mind.

One cannot deal with a problem with the same thinking that creates it.