The possession of power inevitably spoils the free use of reason.

Physicians think they are doing something for you by labeling what you have as a disease

There is no virtue in penance and fasting which waste the body; they are only fanatical and monkish.

Thoughts without content are empty, intuitions without concepts are blind... The understanding can intuit nothing, the senses can think nothing. Only through their union can knowledge arise.

I learned to honor human beings, and I would find myself far more useless than the common laborer if I did not believe that this consideration could impart to all others a value establishing the rights of humanity.

A single line in the Bible has consoled me more than all the books I ever read besides.

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.