Click on the phrases to see them in context. The original texts by Immanuel Kant and David Hume are available from the Gutenberg Projet.

And, indeed, how should it be possible, merely by the aid of the unity of consciousness--which we cognize only for the reason that it is indispensable to the possibility of experience--to pass the bounds of experience (our existence in this life); and to extend our cognition to the nature of all thinking beings by means of the empirical--but in relation to every sort of intuition, perfectly undetermined--proposition, "I think"?