First doubt, then inquire, then discover. This has been the process with all our great thinkers.

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.

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.

The duty of a philosopher is clear. He must take every pain to ascertain the truth; and, having arrived at a conclusion, he should noise it abroad far and wide, utterly regardless of what opinions he shocks.

When the interval between the intellectual classes and the practical classes is too great, the former will possess no influence, the latter will reap no benefit.

Men are made uneasy; they flinch; they cannot bear the sudden light; a general restlessness supervenes; the face of society is disturbed, or perhaps convulsed; old interests and old beliefs have been destroyed before new ones have been created. These symptoms are the precursors of revolution; they have preceded all the great changes through which the world has passed.

That the system of morals propounded in the New Testament contained no maxim which had not been previously enunciated, and that some of the most beautiful passages in the apostolic writings are quotations from Pagan authors, is well known to every scholar... To assert that Christianity communicated to man moral truths previously unknown, argues on the part of the asserted either gross ignorance or wilful fraud.