Human freedom is realised in the adoption of humanity as an end in itself, for the one thing that no-one can be compelled to do by another is to adopt a particular end. - 'Metaphysical Principles of Virtue
The means employed by Nature to bring about the development of all the capacities of men is their antagonism in society, so far as this is, in the end, the cause of a lawful order among men.
[S]uppose the mind of [a] friend of humanity were clouded over with his own grief, extinguishing all sympathetic participation in the fate of others; he still has the resources to be beneficent to those suffering distress, but the distress of others does not touch him because he is sufficiently busy with his own; and now, where no inclination any longer stimulates him to it, he tears himself out of his deadly insensibility and does the action without any inclination, solely from duty.
The schematicism by which our understanding deals with the phenomenal world ... is a skill so deeply hidden in the human soul that we shall hardly guess the secret trick that Nature here employs.
I freely admit that the remembrance of David Hume was the very thing that many years ago first interrupted my dogmatic slumber and gave a completely different direction to my researches in the field of speculative philosophy.
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.