The Study of philosophy is not that we may know what men have thought, but what the truth of things is.

Three things are necessary for the salvation of man: to know what he ought to believe; to know what he ought to desire; and to know what he ought to do.

Wonder was the motive that led people to philosophy ... wonder is a kind of desire in knowledge. It is the cause of delight because it carries with it the hope of discovery.

The greatest kindness one can render to any man consists in leading him from error to truth.

One cannot use an evil action with reference to a good intention.

Man has free choice, or otherwise counsels, exhortations, commands, prohibitions, rewards and punishments would be in vain.

To bear with patience wrongs done to oneself is a mark of perfection, but to bear with patience wrongs done to someone else is a mark of imperfection and even of actual sin.