The trouble with most people is that they think with their hopes or fears or wishes rather than with their minds.

The time when you need to do something is when no one else is willing to do it, when people are saying it can't be done.

The great snare of thought is uncritical acceptance of irrational assumptions.

Civilizaton is the interval between Ice Ages.

Underneath all civilization, ancient or modern, moved and still moves a sea of magic, superstition, and sorcery. Perhaps they will remain when the works of our reason have passed away.

I came to think of myself, not as a dance and chaos of molecules, but as a brief and minute portion of that majestic process

The experience of the past lives little doubt that every economic system must sooner or later rely upon some form of the profit motive to stir individuals and groups to productivity. Substitutes like slavery, police supervision, or ideological enthusiasm prove too unproductive, too expensive, or too transient.