The wise man can change his mind; the stubborn one, never.
Laws always lose in energy what the government gains in extent.
In the natural state no concept of God can arise, and the false one which one makes for himself is harmful. Hence the theory of natural religion can be true only where there is no science; therefore it cannot bind all men together.
So act that anything you do may become universal law.
All appearances are real and negatio; sophistical: All reality must be sensation.
Our intellect does not draw its laws from nature, but it imposes its laws upon nature.
Freedom in the practical sense is the independence of the power of choice from necessitation by impulses of sensibility.
Nature even in chaos cannot proceed otherwise than regularly and according to order.
The wish to talk to God is absurd. We cannot talk to one we cannot comprehend – and we cannot comprehend God; we can only believe in Him.
It is presumed that there exists a great unity in nature, in respect of the adequacy of a single cause to account for many different kinds of consequences.
Genius is the ability to independently arrive at and understand concepts that would normally have to be taught by another person.
There is a limit where the intellect fails and breaks down, and this limit is where the questions concerning God and freewill and immortality arise.
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.
Two things strike me dumb: the infinite starry heavens, and the sense of right and wrong in man.
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.
He who has made great moral progress ceases to pray.
An organized product of nature is that in which all the parts are mutually ends and means.
Philosophy stands in need of a science which shall determine the possibility, principles, and extent of human knowledge à priori.
Ours is an age of criticism, to which everything must be subjected.
Perpetual Peace is only found in the graveyard.
Ich solle niemals anders verfahren, als so, dass ich auch wollen k o« nne, meine Maxime solle ein allgemeines Gesetz werden. I ought never to act except in such a way that I can also will that my maxim should become a universal law.