Page:Ferrier's Works Volume 1 - Institutes of Metaphysic (1875 ed.).djvu/286

258PROP. X.————

1. The truth of this proposition, although dimly surmised and vaguely contended for in the higher schools of speculation, has never been proved until now. Two premises were required for its proof: it was requisite to show, first, that some one thing, or rather element must be known along with all the presentations of sense; and, secondly, that this thing, or element, could not be known as material. These, and only these, are competent data of proof in this case. But no system hitherto propounded has ever distinctly shown what this one thing or element is, or even that there is any such thing or element; much less has any previous system ever proved that this element could not be known to be material. The data of proof, therefore, were wanting in all previous systems—and, consequently, this proposition, to whatever extent, or in whatever form, it may have been enunciated, has until now remained undemonstrated. Neither of the two premises would, without the other, have been of any avail in proving it. We might show that self must be known along with all the presentations of sense; but if self could be known as material, or as a presentation of sense, no ground would be afforded for the inference that mere objects of sense could never be objects of cognition. Again,