Truths emerge from facts, but they dip forward into facts again and add to them; which facts again create or reveal new truth (the word is indifferent) and so on indefinitely. The 'facts' themselves meanwhile are not true. They simply are. Truth is the function of the beliefs that start and terminate among them.

Plasticity, then, in the wide sense of the word, means the possession of a structure weak enough to yield to an influence, but strong enough not to yield all at once. Each relatively stable phase of equilibrium in such a structure is marked by what we may call a new set of habits.

An enormous mass of experience, both of homeopathic doctors and their patients, is invoked in favor of the efficacy of these remedies and doses.

Good-humor is a philosophic state of mind; it seems to say to Nature that we take her no more seriously than she takes us. I maintain that one should always talk of philosophy with a smile.

Keep the faculty of effort alive in you by a little gratuitous exercise every day.

Belief is desecrated when given to unproved and unquestioned statements for the solace and private pleasure of the believer . . . It is wrong always, everywhere, and for every one, to believe anything upon insufficient evidence.

We are doomed to cling to a life even while we find it unendurable.