The only race I know is the human one.

Unlimited competition leads to a huge waste of labor, and to that crippling of the social consciousness of individuals.

This change in the conception of reality is the most profound and the most fruitful that physics has experienced since the time of Newton. Refering to James Clerk Maxwell's contributions to physics.

Imagination is more important than knowledge. Knowledge is limited. Imagination encircles the world.

Certainly there are things worth believing. I believe in the brotherhood of man and the uniqueness of the individual. But if you ask me to prove what I believe, I can't. You know them to be true but you could spend a whole lifetime without being able to prove them. The mind can proceed only so far upon what it knows and can prove. There comes a point where the mind takes a leap—call it intuition or what you will—and comes out upon a higher plane of knowledge, but can never prove how it got there. All great discoveries have involved such a leap.

Before God we are all equally wise - and equally foolish.

In conclusion I wish to say that in working at the problem here dealt with I have had the loyal assistance of my friend and colleague M. Besso, and that I am indebted to him for several valuable suggestions.