Act in such a way that you treat humanity, whether in your own person or in the person of any other, never merely as a means to an end, but always at the same time as an end.
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.
Every man is to be respected as an absolute end in himself; and it is a crime against the dignity that belongs to him as a human being, to use him as a mere means for some external purpose.
At some future day it will be proved, I cannot say when and where, that the human soul is, while in earth life, already in an uninterrupted communication with those living in another world.
A science of all these possible kinds of space [the higher dimensional ones] would undoubtedly be the highest enterprise which a finite understanding could undertake in the field of geometry... If it is possible that there could be regions with other dimensions, it is very likely that God has somewhere brought them into being.