So long as the mental and moral instruction of man is left solely in the hands of hired servants of the public--let them be teachers of religion, professors of colleges, authors of books, or editors of journals or periodical publications, dependent upon their literary incomes for their daily bread, so long shall we hear but half the truth; and well if we hear so much. Our teachers, political, scientific, moral, or religious; our writers, grave or gay, are compelled to administer to our prejudices and to perpetuate our ignorance.

The man possessed of a dollar, feels himself to be not merely one hundred cents richer, but also one hundred cents better, than the man who is penniless; so on through all the gradations of earthly possessions - the estimate of our own moral and political importance swelling always in a ratio exactly proportionate to the growth of our purse.

it is not that religion is merely useless, it is mischievous. It is mischievous by its idle terrors; it is mischievous by its false morality; it is mischievous by its hypocrisy; by its fanaticism; by its dogmatism; by its threats; by its hopes; by its promises.

There is but one honest limit to the rights of a sentient being; it is where they touch the rights of another sentient being.

The sciences have ever been the surest guides to virtue.

It is in vain that we would circumscribe the power of one half of our race, and that half by far the most important and influential.

Knowledge signifies things known. Where there are no things known, there is no knowledge. Where there are no things to be known, there can be no knowledge. We have observed that every science, that is, every branch of knowledge, is compounded of certain facts, of which our sensations furnish the evidence. Where no such evidence is supplied, we are without data; we are without first premises; and when, without these, we attempt to build up a science, we do as those who raise edifices without foundations. And what do such builders construct? Castles in the air.