Act so that the maxim of your act could be made the principle of a universal law.
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.
Nothing is divine but what is agreeable to reason.
An action is essentially good if the motive of the agent be good, regardless of the consequences.
Do what is right, though the world may perish.
There can be no doubt that all our knowledge begins with experience.