Two things strike me dumb: the infinite starry heavens, and the sense of right and wrong in man.

Life is the faculty of spontaneous activity, the awareness that we have powers.

But where only a free play of our presentational powers is to be sustained, as in the case of pleasure gardens, room decoration, all sorts of useful utensils, and so on, any regularity that has an air of constraint is [to be] avoided as much as possible. That is why the English taste in gardens, or the baroque taste in furniture, carries the imagination's freedom very far, even to the verge of the grotesque, because it is precisely this divorce from any constraint of a rule that the case is posited where taste can show its greatest perfection in designs made by the imagination.

There can be no doubt that all our knowledge begins with experience.

That Logic has advanced in this sure course, even from the earliest times, is apparent from the fact that, since Aristotle, it has been unable to advance a step, and thus to all appearance has reached its completion.

I feel a complete thirst for knowledge and an eager unrest to go further in it as well as satisfaction at every acquisition. There was a time when I believed that this alone could constitute the honor of mankind, and I had contempt for the ignorant rabble who know nothing.

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.