Page:Ferrier's Works Volume 1 - Institutes of Metaphysic (1875 ed.).djvu/418

390PROP. XXII.———— 6. Let these be now placed in contrast with the necessary condition of all knowledge to which expression was given in the first proposition of this system. Let the man, as before, suppose himself to be gazing on the tree. That which he is cognisant of is, as before, himself-seeing-the-tree. Let us now suppose the self which he is cognisant of to be exchanged for something else, and that some mode of apprehension different from self-consciousness comes into play—would the man, in that case, continue to have any cognisance of the tree? Certainly he would not. No cognition of the tree, or of anything else, would now be possible. Withhold any of a man's senses from his cognisance when he is conversant with external things, and he will still be able to apprehend them, provided you give him other modes of apprehension. But withhold a man's self from his cognisance when he is conversant with external things, and he shall not be able to apprehend them intelligently,—give him what substitute and what endowments you please in place of the self which has been withdrawn from his cognition. It is thus obvious that, while it is possible for intelligence to know things without knowing them by means of such senses as ours, inasmuch as it may know them in other ways of which we can form no conception, it is impossible for any intelligence to know them without being cognisant of itself at the same time. Hence