The three main medieval points of view regarding universals are designated by historians as realism, conceptualism, and nominalism. Essentially these same three doctrines reappear in twentieth-century surveys of the philosophy of mathematics under the new names logicism, intuitionism, and formalism.

Confusion of sign and object is original sin coeval with the word.

Life is agid, life is fulgid. Life is what the least of us make most of us feel the least of us make the most of. Life is a burgeoning, a quickening of the dim primordial urge in the murky wastes of time.

The variables of quantification, 'something,' 'nothing,' 'everything,' range over our whole ontology, whatever it may be; and we are convicted of a particular ontological presupposition if, and only if, the alleged presuppositum has to be reckoned among the entities over which our variables range in order to render one of our affirmations true.

Creatures inveterately wrong in their inductions have a pathetic but praise-worthy tendency to die before reproducing their kind.

Some may find comfort in reflecting that the distinction between an eliminative and an explicative physicalism is unreal.

The lore of our fathers is a fabric of sentences. In our hands it develops and changes, through more or less arbitrary and deliberate revisions and additions of our own, more or less directly occasioned by the continuing stimulation of our sense organs. It is a pale gray lore, black with fact and white with convention. But I have found no substantial reasons for concluding that there are any quite black threads in it, or any white ones.