It must be wonderful to be seventeen, and to know everything. - Arthur C. Clarke

For Jan was still suffering from the romantic illusion–the cause of so much misery and so much poetry–that every man has only one real love in his life.

The dinosaurs disappeared because they could not adapt to their changing environment. We shall disappear if we cannot adapt to an environment that now contains spaceships, computers — and thermonuclear weapons.

They will have time enough, in those endless aeons, to attempt all things, and to gather all knowledge ... no Gods imagined by our minds have ever possessed the powers they will command ... But for all that, they may envy us, basking in the bright afterglow of Creation; for we knew the Universe when it was young.