Without man and his potential for moral progress, the whole of reality would be a mere wilderness, a thing in vain, and have no final purpose.

The death of dogma is the birth of morality.

...[T]o be unfaithful to my maxim of prudence may often be very advantageous to me, although to abide by it is certainly safer.

Two things fill the mind with ever-increasing wonder and awe, the more often and the more intensely the mind of thought is drawn to them: the starry heavens above me and the moral law within me.

If we were to suppose that mankind never can or will be in a better condition, it seems impossible to justify by any kind of theodicy the mere fact that such a race of corrupt beings could have been created on earth at all.

Act in such a way that you treat humanity, whether in your own person or in the person of any other, never merely as a means to an end, but always at the same time as an end.

The people naturally adhere most to doctrines which demand the least self-exertion and the least use of their own reason, and which can best accommodate their duties to their inclinations.

An action, to have moral worth, must be done from duty.

To behold virtue in her proper form is nothing else but to contemplate morality stripped of all admixture of sensible things and of every spurious ornament of reward or self-love. How much she then eclipses everything else that appears charming to the affections, every one may readily perceive with the least exertion of his reason, if it be not wholly spoiled for abstraction.