Namely, we have no right to believe a thing true because everybody says so unless there are good grounds for believing that some one person at least has the means of knowing what is true, and is speaking the truth so far as he knows it.

Our lives our guided by that general conception of the course of things which has been created by society for social purposes.

No simplicity of mind, no obscurity of station, can escape the universal duty of questioning all that we believe.

The danger to society is not merely that it should believe wrong things, though that is great enough; but that it should become credulous, and lose the habit of testing things and inquiring into them; for then it must sink back into savagery.

When an action is once done, it is right or wrong for ever; no accidental failure of its good or evil fruits can possibly alter that.

There is no scientific discoverer, no poet, no painter, no musician, who will not tell you that he found ready made his discovery or poem or picture — that it came to him from outside, and that he did not consciously create it from within.

A little reflection will show us that every belief, even the simplest and most fundamental, goes beyond experience when regarded as a guide to our actions.