Give me matter, and I will construct a world out of it!
The main point of enlightenment is man's release from his self-caused immaturity, primarily in matters of religion.
Dignity is a value that creates irreplaceability.
What can I know? What ought I to do? What can I hope?
Science is organized knowledge. Wisdom is organized life.
The touchstone of everything that can be concluded as a law for a people lies in the question whether the people could have imposed such a law on itself.
Experience without theory is blind, but theory without experience is mere intellectual play.
Every man is to be respected as an absolute end in himself: and it is a crime against the dignity that belongs to him as a human being to use him as a mere means for some external purpose.
We are not rich by what we possess but by what we can do without.
The people naturally adhere most to doctrines which demand the least self-exertion and the least use of their own reason, and which can best accommodate their duties to their inclinations.
It is not God's will merely that we should be happy, but that we should make ourselves happy.
But, though all our knowledge begins with experience, it by no means follows that all arises out of experience.
Everything in nature acts in conformity with law.
Immaturity is the incapacity to use one's intelligence without the guidance of another.
But although all our knowledge begins with experience, it does not follow that it arises from experience.
The death of dogma is the birth of reality.
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?
The enjoyment of power inevitably corrupts the judgement of reason, and perverts its liberty.
The true religion is to be posited not in the knowledge or confession of what God allegedly does or has done for our salvation, but in what we must do to become worthy of this.
In every department of physical science there is only so much science, properly so-called, as there is mathematics.