At 60 the sexual preoccupation, when it hits you, seems sometimes sharper, as if it were an elderly malady, like gout.

Keep going; never stop; sit tight; Read something luminous at night.

I am not quite a poet but I am something of the kind.

The product of the scientific imagination is a new vision of relations - like that of artistic imagination.

Only the curious will learn and only the resolute will overcome the obstacles to learning. The quest quotient has always excited me more than the intelligence quotient.

I find more and more that I am a man of the 1920s. I still expect something exciting. Drinks, animated conversation, gaiety: the uninhibited exchange of ideas.

The cruelest thing that has happened to Lincoln since he was shot by Booth was to fall into the hands of Carl Sandburg.