It's what we think we know that keeps us from learning.

It is what we know already that often prevents us from learning.

The experimenter who does not know what he is looking for will not understand what he finds.

When we meet a fact which contradicts a prevailing theory, we must accept the fact and abandon the theory, even when the theory is supported by great names and generally accepted.

Man can learn nothing unless he proceeds from the known to the unknown.

The terrain is everything; the germ is nothing.

Art is 'I'; science is 'we'.

A fact in itself is nothing. It is valuable only for the idea attached to it, or for the proof which it furnishes.

Those who do not know the torment of the unknown cannot have the joy of discovery.

Science increases our power in proportion as it lowers our pride.

All the vital mechanisms, varied as they are, have only one object, that of preserving constant the conditions of life in the internal environment.

No one book of scripture can be understood by itself, any more than any one part of a tree or member of the body can be understood without reference to the whole of which it is a part.

Flying is not only the art of the birds, but it is also the art of the artists!

The world does not need tourists who ride by in a bus clucking their tongues. The world as it is needs those who will love it enough to change it, with what they have, where they are.

Life is the great indulgence - death the great abstinence. Therefore, make the most of life here and now!

Symptoms of ethical, political and economic impoverishment are all around us.

If the people are to be the final tribunal then they must vote for what is right rather than according to their own selfish interests, else we are treading the path of danger.

When you arrive at a certain level it's very easy to say yes: that is the moment to learn to say no.

Self-pity dries up our sympathy for others.

Some things get written more quickly than others, but I can't really measure degrees of difficulty.

Frightened, I jump up from the bank, the struggle begins anew. Bitterness has returned. I am not Pan in the reed, I am merely a human being and want to climb a few steps, but really climb them.