The joy of discovery is certainly the liveliest that the mind of man can ever feel.

The terrain is everything; the germ is nothing.

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

In the patient who succumbed, the cause of death was evidently something which was not found in the patient who recovered; this something we must determine, and then we can act on the phenomena or recognize and foresee them accurately. But not by statistics shall we succeed in this; never have statistics taught anything, and never can they teach anything about the nature of the phenomenon.

We must keep our freedom of mind, ... and must believe that in nature what is absurd, according to our theories, is not always impossible.

Proof that a given condition always precedes or accompanies a phenomenon does not warrant concluding with certainty that a given condition is the immediate cause of that phenomenon. It must still be established that when this condition is removed, the phenomen will no longer appear.

A contemporary poet has characterized this sense of the personality of art and of the impersonality of science in these words,-'Art is myself; science is ourselves. '