Scientific principles and laws do not lie on the surface of nature. They are hidden, and must be wrested from nature by an active and elaborate technique of inquiry.
The path of least resistance and least trouble is a mental rut already made. It requires troublesome work to undertake the alternation of old beliefs.
Skepticism: the mark and even the pose of the educated mind.
The good man is the man who, no matter how morally unworthy he has been, is moving to become better.
Man lives in a world of surmise, of mystery, of uncertainties.
One lives with so many bad deeds on one's conscience and some good intentions in one's heart.
