“For if we regard space and time as properties that must, as regards their possibility, be found in things in themselves, [...] then we really cannot blame the good Bishop Berkeley for degrading bodies to mere illusion. Nay, even our own existence, which would thus be made dependent on the self-subsistent reality of a non-entity such as time, would, along with this time, be changed into mere illusion - an absurdity of which hitherto no one has been guilty.”

“Space and time are the framework within which the mind is constrained to construct its experience of reality.”

“Without man and his potential for moral progress, the whole of reality would be a mere wilderness, a thing in vain, and have no final purpose.”

“Man, and in general every rational being, exists as an end in himself, not merely as a means for arbitrary use by this or that will: he must in all his actions, whether they are directed to himself or to other rational beings, always be viewed at the same time as an end.”

“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 to unite in a permanent religious institution which is not to be subject to doubt before the public even in the lifetime of one man, and thereby to make a period of time fruitless in the progress of mankind toward improvement, thus working to the disadvantage of posterity - that is absolutely forbidden. For himself (and only for a short time) a man may postpone enlightenment in what he ought to know, but to renounce it for posterity is to injure and trample on the rights of mankind.”

“An age cannot bind itself and ordain to put the succeeding one into such a condition that it cannot extend its (at best very occasional) knowledge , purify itself of errors, and progress in general enlightenment. That would be a crime against human nature, the proper destination of which lies precisely in this progress and the descendants would be fully justified in rejecting those decrees as having been made in an unwarranted and malicious manner.The touchstone of everything that can be concluded as a law for a people lies in the question whether the people could have imposed such a law on itself.”