He who knows most believes the least.

Even in an advanced stage of civilization, there is always a tendency to prefer those parts of literature which favor ancient prejudices, rather than those which oppose them; and in cases where this tendency is very strong, the only effect of great learning will be to supply the materials which may corroborate old errors and confirm old superstitions. In our time such instances are not uncommon; and we frequently meet with men whose erudition ministers to their ignorance, and who, the more they read the less they know.

The clergy, with a few honorable exceptions, have in all modern countries been the avowed enemies of the diffusion of knowledge, the danger of which to their own profession they, by a certain instinct, seem always to have perceived.

The faculty of art is to change events; the faculty of science is to foresee them. The phenomena with which we deal are controlled by art; they are predicted by science.

Men and women range themselves into three classes or orders of intelligence; you can tell the lowest class by their habit of always talking about persons; the next by the fact that their habit is always to converse about things; the highest by their preference for the discussion of ideas.

The great enemy of knowledge is not error, but inertness. All that we want is discussion; and then we are sure to do well, no matter what our blunders may be. One error conflicts with another, each destroys its opponent, and truth is evolved.

Sir, the slowness of genius is hard to bear, but the slowness of mediocrity is insufferable.