Enlightenment is man's emergence from his self-incurred immaturity.
It is precisely in knowing its limits that philosophy consists.
The light dove, cleaving the air in her free flight, and feeling its resistance, might imagine that its flight would be still easier in empty space.
Animals... are there merely as a means to an end. That end is man.
It is not God's will merely that we should be happy, but that we should make ourselves happy
A single line in the Bible has consoled me more than all the books I ever read besides.