In the midst of difficulty lies opportunity.

The series of integers is obviously an invention of the human mind, a self-created tool which simplifies the ordering of certain sensory experiences.

But if the longing for the achievement of the goal is powerfully alive within us, then shall we not lack the strength to find the means for reaching the goal and for translating it into deeds.

If men as individuals surrender to the call of their elementary instincts, avoiding pain and seeking satisfaction only for their own selves, the result for them all taken together must be a state of insecurity, of fear, and of promiscuous misery.

Every one who is seriously involved in the pursuit of science becomes convinced that a spirit is manifest in the laws of the Universe-a spirit vastly superior to that of man, and one in the face of which we with our modest powers must feel humble.

I think 99 times and find nothing. I stop thinking, swim in the silence, and the truth comes to me.

Curiosity is a delicate little plant that, aside from stimulation, stands mainly in need of freedom.