Natural science physics contains in itself synthetical judgments a priori, as principles. ... Space then is a necessary representation a priori, which serves for the foundation of all external intuitions.
Freedom is independence of the compulsory will of another, and in so far as it tends to exist with the freedom of all according to a universal law, it is the one sole original inborn right belonging to every man in virtue of his humanity.
Even the song of birds, which we can bring under no musical rule, seems to have more freedom, and therefore more for taste, than a song of a human being which is produced in accordance with all the rules of music; for we very much sooner weary of the latter, if it is repeated often and at length. Here, however, we probably confuse our participation in the mirth of a little creature that we love, with the beauty of its song; for if this were exactly imitated by man (as sometimes the notes of the nightingale are) it would seem to our ear quite devoid of taste.
The universal and lasting establishment of peace constitutes not merely a part, but the whole final purpose and end of the science of right as viewed within the limits of reason.
Enlightenment is the liberation of man from his self-caused state of minority... Supere aude! Dare to use your own understanding!is thus the motto of the Enlightenment.
I learned to honor human beings, and I would find myself far more useless than the common laborer if I did not believe that this consideration could impart to all others a value establishing the rights of humanity.
Through laziness and cowardice a large part of mankind, even after nature has freed them from alien guidance, gladly remain immature. It is because of laziness and cowardice that it is so easy for others to usurp the role of guardians. It is so comfortable to be a minor!
The ideal of the supreme being is nothing but a regulative principle of reason which directs us to look upon all connection in the world as if it originated from an all-sufficient necessary cause.