Real life consists of the tensions produced by the incompatibility of opposites, each of which is needed

I cannot predict the wind but I can have my sail ready.

The modern world tends to be skeptical about everything that makes demands on man's higher faculties. But it is not at all skeptical about skepticism, which demands hardly anything.

If, however, economic ambitions are good servants, they are bad masters

The generosity of the Earth allows us to feed all mankind; we know enough about ecology to keep the Earth a healthy place; there is enough room on the Earth, and there are enough materials, so that everybody can have adequate shelter; we are quite competent enough to produce sufficient supplies of necessities so that no one need live in misery.

If I limit myself to knowledge that I consider true beyond doubt, I minimize the risk of error but I maximize, at the same time, the risk of missing out on what may be the subtlest, most important and most rewarding things in life.

Never let an inventor run a company. You can never get him to stop tinkering and bring something to market