I do not believe that a moral philosophy can ever be founded on a scientific basis. … The valuation of life and all its nobler expressions can only come out of the soul’s yearning toward its own destiny. Every attempt to reduce ethics to scientific formulas must fail. Of that I am perfectly convinced.

The Universe is difficult to comprehend because it is obvious.

On the other hand, the concept owes its meaning and its justification exclusively to the totality of the sense impressions which we associate with it.

We cannot get to where we dream of being tomorrow unless we change our thinking today.

If I had known they were going to do this, I would have become a shoemaker.

I do not believe in the God of theology who rewards good and punishes evil.

Imagination is the highest form of research.