What we call little things are merely the causes of great things; they are the beginning, the embryo, and it is the point of departure which, generally speaking, decides the whole future of an existence. One single black speck may be the beginning of gangrene, of a storm, of a revolution.

The best path through life is the highway.

Our life is nothing, it is true, but our life is divine. A breath of nature annihilates us, but we surpass nature in penetrating far beyond her vast phantasmagoria to the changeless and the eternal.

Tell me what you feel in your room when the full moon is shining in upon you and your lamp is dying out, and I will tell you how old you are, and I shall know if you are happy.

Heroism is the brilliant triumph of the soul over the flesh - over fear...Heroism is the dazzling and glorious concentration of courage.

The great majority of men are but tangled skeins, imperfect keyboards, so many specimens of restless or stagnant chaos--and what makes their situation almost hopeless is the fact that they take pleasure in it. There is no curing a sick man who believes himself in health.

[T]he habit of scientific analysis ... exhausts the material offered to it.