The number of natural hypothesis that can explain any given phenomena is infinite.

The only justification for our concepts and systems of concepts is that they serve to represent the complex of our experiences; beyond this they have not legitimacy.

All the fifty years of conscious brooding have brought me no closer to answer the question, "What are light quanta?" Of course today every rascal thinks he knows the answer, but he is deluding himself.

Imagination is vastly more important than intelligence.

But their intervention makes our acts to serve ever less merely the immediate claims of our instincts.

Those who have the privilege to know have the duty to act.

Do you remember how electrical currents and 'unseen waves' were laughed at? The knowledge about man is still in its infancy.