We are on the earth, and they tell us of heaven; we are human beings, and they tell us of angels and devils; we are matter, and they tell us of spirit; we have five senses whereby to admit truths, and a reasoning faculty by which to build our belief upon them; and they tell us of dreams dreamed thousands of years ago, which our experience flatly contradicts.

Many are called impious, not for having a worse, but a different religion from their neighbors; and many atheistical, not for the denying of God, but for thinking somewhat peculiarly concerning him.

Credulity is always a ridiculous, often a dangerous failing: it has made of many a clever man, a fool; and of many a good man, a knave.

Persecution for opinion is the master vice of society.

I am neither Jew nor Gentile, Mohammedan nor Theist; I am but a member of the human family, and would accept of truth by whomsoever offered -- that truth which we can all find, if we will but seek in things, not in words; in nature, not in human imagination; in our own hearts, not in temples made with hands.

Trust me, there are as many ways of living as there are men, and one is no more fit to lead another, than a bird to lead a fish, or a fish a quadruped.

... we have broken down the self-respecting spirit of man with nursery tales and priestly threats, and we dare to assert, that inproportion as we have prostrated our understanding and degraded our nature, we have exhibited virtue, wisdom, and happiness, in our words, our actions, and our lives!