If we knew that god exists, such knowledge would make morality impossible. For, if we acted morally from fear or fright, or confident of a reward, then this would not be moral. It would be enlightened selfishness.
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.
The greatest problem for the human species, the solution of which nature compels him to seek, is that of attaining a civil society which can administer justice universally.
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.
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.