Anybody can find infinite Mandelbrot figures in his navel.

Give fear no hold on you. Keep sinews loose and senses open, ready at every instant to flow with the rush of action.

A fanatic is a man who, when he's lost sight of his purpose, redoubles his effort.

He had seen too much of the cosmos to have any great faith in man's ability to understand it.

Will none wipe the sneer off the face of the cosmos?

A fanatic's willingness to kill or be killed in the service of a cause cannot prove the rightness of that cause.

Colonization means potential immortality for the human genus. Man's safety on Earth was never great, and it dwindles hourly. Disarmament, even world government, will not guarantee survival in an age when population presses natural resources to the limit and when the knowledge of how to work mischief on a planetary scale is ever more widely diffused among peoples who may grow ever more desperate.