Our theories are wedged and controlled as nothing else is. Yet sometimes alternative theoretic formulas are equally compatible with all the truths we know, and then we choose between them for subjective reasons. We choose the kind of theory to which we are already partial: we follow 'elegenace' or 'economy'

We, the lineal representatives of the successful enactors of one scene of slaughter after another, must, whatever more pacific virtues we may also possess, still carry about with us, ready at any moment to burst into flame, the smoldering and sinister traits of character by means of which they lived through so many massacres, harming others, but themselves unharmed.

Do something everyday for no other reason than you would rather not do it, so that when the hour of dire need draws nigh, it may find you not unnerved and untrained to stand the test.

We are proud of a human nature that could be so passionately extreme, but we shrink from advising others to follow the example.

Regarding mutual tolerance: It is negative in one sense, but positive in another. It absolutely forbids us to be forward in pronouncing on the meaninglessness of forms of existence other than our own; and it commands us to tolerate, respect, and indulge those whom we see harmlessly interested and happy in their own ways, however unintelligible these may be to us. Hands off.

Faith is synonymous with working hypothesis.

The desire to gain wealth and the fear to lose it are our chief breeders of cowardice and propagators of corruption.