New knowledge is the most valuable commodity on earth. The more truth we have to work with, the richer we become.

If a sign is useless, it is meaningless. That is the point of Occam's maxim.

Faith which does not doubt is dead faith.

The stuff of the world may be called physical or mental or both or neither, as we please; in fact, the words serve no purpose.

Skeptical scrutiny is the means, in both science and religion, by which deep insights can be winnowed from deep nonsense.

Everything we see and seam, is nothing but a dream within a dream.

The reasonable man adapts himself to the world; the unreasonable man persists in trying to adapt the world to himself. Therefore, all progress depends on the unreasonable man.

For the world is a sum of appearances; and there must therefore be some transcendental ground of the appearances, that is, a ground which is thinkable only by the pure understanding.

All life operates through a mechanism, and the higher the form of life the more complex, sure and flexible the mechanism. This fact alone should save us from opposing life and mechanism, thereby reducing the latter to unintelligent automatism and the former to aimless splurge.

Maturity is a bitter disappointment for which no remedy exists, unless laughter can be said to remedy anything.