The best doctor is the one you run to and can't find.

Good music is very close to primitive language.

When superstition is allowed to perform the task of old age in dulling the human temperament, we can say goodbye to all excellence in poetry, in painting, and in music.

There are three principal means of acquiring knowledge... observation of nature, reflection, and experimentation. Observation collects facts reflection combines them experimentation verifies the result of that combination.

No man has received from nature the right to command his fellow human beings.