“It is certainly a bad sign of common sense to appeal to it as a witness.”

From such crooked timber as humanity is made of, no straight thing was ever constructed.

We can never, even by the strictest examination, get completely behind the secret springs of action.

I have therefore found it necessary to deny knowledge, in order to make room for faith.

You must, therefore you can. A free will and a will subject to moral laws are one and the same thing.

All human cognition begins with intuitions, proceeds from thence to conceptions, and ends with ideas.

All so-called moral interest consists simply in respect for the law.

War seems to be ingrained in human nature, and even to be regarded as something noble to which man is inspired by his love of honor, without selfish motives.

Human beings are never to be treated as a means but always as ends.

To be is to do.

But only he who, himself enlightened, is not afraid of shadows.

Rules for happiness: something to do, someone to love, something to hope for.

Things which as effects presuppose others as causes cannot be reciprocally at the same time causes of these.

Freedom, is a property of all rational beings.

Nature is beautiful because it looks like Art; and Art can only be called beautiful if we are conscious of it as Art while yet it looks like Nature.

The enjoyment of power inevitably corrupts the judgement of reason, and perverts its liberty.

Morality is not properly the doctrine of how we may make ourselves happy, but how we may make ourselves worthy of happiness.