Imagination rules the earth

The man who regards his own life and that of his fellow-creatures as meaningless is not merely unfortunate but almost disqualified for life.

The real problem is in the hearts and minds of men. It is not a problem of physics but of ethics. It is easier to denature plutonium than to denature the evil spirit of man.

Time is what the clock says.

From a certain temperature on, the molecules 'condense' without attractive forces; that is, they accumulate at zero velocity. The theory is pretty, but is there some truth in it.

The intellect has little to do on the road to discovery. There comes a leap in consciousness, call it Intuition or what you will, the solution comes to you and you don't know how or why.

The wing structure of the hornet, in relation to its weight, is not suitable for flight, but he does not know this and flies anyway.