The character of the species, as it is indicated by the experience of all ages and all peoples, is this: that taken collectively (the human race as o… - Immanuel Kant

Human reason has this peculiar fate that in one species of its knowledge it is burdened by questions which, as prescribed by the very nature of reason itself, it is not able to ignore, but which, as transcending all its powers, it is also not able to answer.

...happiness is not an ideal of reason but of imagination, resting solely on empirical grounds.

I do not say that things in themselves possess a quantity, that their reality possesses a degree, their existence a connection of accidents in a substance, etc. This nobody can prove, because such a synthetic connection from mere concepts, without any reference to sensuous intuition on the one side or connection of such intuition in a possible experience on the other, is absolutely impossible.