Something of the hermit's temper is an essential element in many forms of excellence, since it enables men to resist the lure of popularity, to pursue important work in spite of general indifference or hostility, and arrive at opinions which are opposed to prevalent errors.

The fundamental concept in social science is Power, in the same sense in which Energy is the fundamental concept in physics.

Love should be a tree whose roots are deep in the earth, but whose branches extend into heaven.

A world full of happiness is not beyond human power to create; the obstacles imposed by inanimate nature are not insuperable. The real obstacles lie in the heart of man, and the cure for these is a firm hope, informed and fortified by thought.

Philosophy, though unable to tell us with certainty what is the true answer to the doubts which it raises, is able to suggest many possiblities which enlarge our thoughts and free them from the tyranny of custom. Thus, while diminishing our feeling of certainty as to what things are, it greatly increases our knowledge as to what the may be; it removes the somewhat arrogant dogmatism of those who have never travelled into the region of liberating doubt, and it keeps alive our sense of wonder by showing familar things in an unfamilar aspect

If everything has a cause, then God must have a cause. If there can be anything without a cause, it may just be the world as God.

Aristotle maintained that women have fewer teeth than men; although he was twice married, it never occurred to him to verify this statement by examining his wives' mouths.