[R]eason is... given to us as a practical faculty, that is, as one that influences the will.

. . . as to moral feeling, this supposed special sense, the appeal to it is indeed superficial when those who cannot think believe that feeling will help them out, even in what concerns general laws: and besides, feelings which naturally differ infinitely in degree cannot furnish a uniform standard of good and evil, nor has any one a right to form judgments for others by his own feelings. . . .

Physicians think they do a lot for a patient when they give his disease a name.

But only he who, himself enlightened, is not afraid of shadows.

Duty is the necessity to act out of reverence for the law.

Better the whole people perish than that injustice be done

Enthusiasm is always connected with the senses, whatever be the object that excites it. The true strength of virtue is serenity of mind, combined with a deliberate and steadfast determination to execute her laws. That is the healthful condition of the moral life; on the other hand, enthusiasm, even when excited by representations of goodness, is a brilliant but feverish glow which leaves only exhaustion and languor behind.