[S]uppose the mind of [a] friend of humanity were clouded over with his own grief, extinguishing all sympathetic participation in the fate of others; he still has the resources to be beneficent to those suffering distress, but the distress of others does not touch him because he is sufficiently busy with his own; and now, where no inclination any longer stimulates him to it, he tears himself out of his deadly insensibility and does the action without any inclination, solely from duty.
The only objects of practical reason are therefore those of good and evil. For by the former is meant an object necessarily desired according to a principle of reason; by the latter one necessarily shunned, also according to a principle of reason.
A man who has tasted with profound enjoyment the pleasure of agreeable society will eat with a greater appetite than he who rode horseback for two hours. An amusing lecture is as useful for health as the exercise of the body.
Human reason has the peculiar fate in one species of its cognitions that it is burdened with questions which it cannot dismiss, since they are given to it as problems by the nature of reason itself, but which it also cannot answer, since they transcend every capacity of human reason.
We assume a common sense as the necessary condition of the universal communicability of our knowledge, which is presupposed in every logic and every principle of knowledge that is not one of skepticism.
The existence of the Bible, as a book for the people, is the greatest benefit which the human race has ever experienced. Every attempt to belittle it is a crime against humanity.
Perhaps a revolution can overthrow autocratic despotism and profiteering or power-grabbing oppression, but it can never truly reform a manner of thinking; instead, new prejudices, just like the old ones they replace, will serve as a leash for the great unthinking mass.