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.

The bad thing of war is, that it makes more evil people than it can take away.

Philosophy stands in need of a science which shall determine the possibility, principles, and extent of human knowledge à priori.

Animals... are there merely as a means to an end. That end is man.

The existence of the Bible is the greatest blessing which humanity ever experienced.

An organized product of nature is that in which all the parts are mutually ends and means.

Things which we see are not by themselves what we see ... It remains completely unknown to us what the objects may be by themselves and apart from the receptivity of our senses. We know nothing but our manner of perceiving them.