When philosophic reason is clear and certain by intuition or necessary induction, no subsequent revelation supported by prophecies or miracles can supersede it.

Thus, experience has ever shown, that education, as well as religion, aristocracy, as well as democracy and monarchy, are, singly, totally inadequate to the business of restraining the passions of men, of preserving a steady government, and protecting the lives, liberties, and properties of the people . . . . Religion, superstition, oaths, education, laws, all give way before passions, interest, and power, which can be resisted only by passions, interest, and power.

Property must be secured, or liberty cannot exist.

Let every sluice of knowledge be opened and set a-flowing.

This would be the best of all possible worlds, if there were no religion in it.

Great is the guilt of an unnecessary war.

A lawyer once told a jury that the person his client stood accused of having killed was about to walk through the courtroom door. When the jurors looked startled, the lawyer asserted that if those jurors had wondered, even for one second that the victim might appear, that belief constituted enough reasonable doubt for them to find his client innocent.