It is not necessary that whilst I live I live happily; but it is necessary that so long as I live I should live honourably.
But although all our knowledge begins with experience, it does not follow that it arises from experience.
Act that your principle of action might safely be made a law for the whole world.
It is not God's will merely that we should be happy, but that we should make ourselves happy.
In law a man is guilty when he violates the rights of others. In ethics he is guilty if he only thinks of doing so.