In the kingdom of ends everything has either a price or a dignity. Whatever has a price can be replaced by something else as its equivalent; on the other hand, whatever is above all price, and therefore admits of no equivalent, has a dignity. But that which constitutes the condition under which alone something can be an end in itself does not have mere relative worth, i.e., price, but an intrinsic worth, i.e., a dignity.

Ingratitude is the essence of vileness.

Enlightenment is man's leaving his self-caused immaturity. Immaturity is the incapacity to use one's intelligence without the guidance of another. Such immaturity is self-caused if it is not caused by lack of intelligence, but by lack of determination and courage to use one's intelligence without being guided by another. Sapere Aude! Have the courage to use your own intelligence! is therefore the motto of the enlightenment.

Humanity is at its greatest perfection in the race of the whites.

Feminine traits are called weaknesses. People joke about them; fools ridicule them; but reasonable persons see very well that those traits are just the tools for the management of men, and for the use of men for female designs.

After death the soul possesses self-consciousness, otherwise, it would be the subject of spiritual death, which has already been disproved. With this self-consciousness necessarily remains personality and the consciousness of personal identity.

The history of the human race, viewed as a whole, may be regarded as the realization of a hidden plan of nature to bring about a political constitution, internally, and for this purpose, also externally perfect, as the only state in which all the capacities implanted by her in mankind can be fully developed.