As agonizing a disease as cancer is, I do not think it can be said that our civilization is threatened by it. ... But a very plausible case can be made that our civilization is fundamentally threatened by the lack of adequate fertility control. Exponential increases of population will dominate any arithmetic increases, even those brought about by heroic technological initiatives, in the availability of food and resources, as Malthus long ago realized.

It seems madness to say, 'We're worried that they're going to become addicted to marijuana' -- there's no evidence whatever that it's an addictive drug, but even if it were, these people are dying, what are we saving them from?

We are the children equally of the Sky and the Earth.

All civilizations become either spacefaring or extinct.

We can always take but never give.

Books are key to understanding the world and participating in a democratic society.

Frederick Douglas taught that literacy is the path from slavery to freedom. There are many kinds of slavery and many kinds of freedom, but reading is still the path.