the leading error of the human mind, - the bane of human happiness - the perverter of human virtue ... is Religion - that dark coinage of trembling ignorance! It is Religion - that poisoner of human felicity! It is Religion - that blind guide of human reason! It is Religion - that dethroner of human virtue! which lies at the root of all the evil and all the misery that pervade the world!

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.

The world is full of religion, and full of misery and crime.

All that I say is, examine, inquire. Look into the nature of things. Search out the grounds of your opinions, the for and against. Know why you believe, understand what you believe, and possess a reason for the faith that is in you.

An opinion, right or wrong, can never constitute a moral offense, nor be in itself a moral obligation. It may be mistaken; it may involve an absurdity, or a contradiction. It is a truth; or it is an error: it can never be a crime or a virtue.

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.

To give liberty to a slave before he understands its value is, perhaps, rather to impose a penalty than to bestow a blessing.