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.
No state at war with another state should engage in hostilities of such a kind as to render mutual confidence impossible when peace will have been made.
At some future day it will be proved, I cannot say when and where, that the human soul is, while in earth life, already in an uninterrupted communication with those living in another world.
Freedom is the alone unoriginated birthright of man, and belongs to him by force of his humanity; and is independence on the will and co-action of every other in so far as this consists with every other person's freedom.
There will always be some people who think for themselves, even among the self-appointed guardians of the great mass who, after having thrown off the yoke of immaturity themselves, will spread about them the spirit of a reasonable estimate of their own value and of the need for every man to think for himself.
Aus so krummen Holze, als woraus der Mensch gemacht ist, kann nichts ganz Gerades gezimmert werden. Out of the crooked timber of humanity, no straight thing can ever be made.
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.
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.
All the interests of my reason, speculative as well as practical, combine in the three following questions: 1. What can I know? 2. What ought I to do? 3. What may I hope?
Enlightenment is man's leaving his self-caused immaturity. Immaturity is the incapacity to use one's intelligence without the guidance of another. Such immaturity is self-caused if it is not caused by lack of intelligence, but by lack of determination and courage to use one's intelligence without being guided by another. Sapere Aude! Have the courage to use your own intelligence! is therefore the motto of the enlightenment.
Men will not understand ... that when they fulfil their duties to men, they fulfil thereby God's commandments; that they are consequently always in the service of God, as long as their actions are moral, and that it is absolutely impossible to serve God otherwise.