Opinions are not to be learned by rote, like the letters of an alphabet, or the words of a dictionary. They are conclusions to be formed, and formed by each individual in the sacred and free citadel of the mind, and there enshrined beyond the arm of law to reach, or force to shake; ay! and beyond the right of impertinent curiosity to violate, or presumptuous arrogance to threaten.

If we bring not the good courage of minds covetous of truth, and truth only, prepared to hear all things, and decide upon all things, according to evidence, we should do more wisely to sit down contented in ignorance, than to bestir ourselves only to reap disappointment.

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.

... the yearly expenses of the existing religious systemexceed in these United States twenty millions of dollars. Twenty millions! For teaching what? Things unseen and causes unknown!... Twenty millions would more than suffice to make us wise; and alas! do they not more than suffice to make us foolish?

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.

... a nation to be strong, must be united; to be united, must be equal in condition; to be equal in condition, must be similar inhabits and feeling; to be similar in habits and feeling, must be raised in national institutions as the children of a common family, and citizens of a common country.

The knowledge of one generation is the ignorance of the next.