here his old polemic against what he calls the system of Plato, though it is doubtful whether Plato would himself have acknowledged it. One would almost say that Aristotle misstated Plato in order to refute him.
The same fate, as if by way of reprisal, has often in modern times befallen the Stagirite, who has repeatedly been misstated, and then censured for what he never had maintained. At the risk, however, of committing fresh injustices of this sort, we will endeavour briefly to sum up his views upon some of the greatest questions which have occupied modern philosophers. First, then, we may ask how would Aristotle have dealt with those problems concerning the existence of Matter, and the reality of the External World, which have been a "shibboleth" in the philosophic world from Bishop Berkeley, through the days of Hume and the Scotch psychologists, down to Kant and Hegel and the extreme idealists of Germany? His utterances on this subject are perhaps chiefly to be found in the third book of his treatise 'On the Soul,' beginning with the fourth chapter. On turning to them we see that he never separates existence from knowledge. "A thing in actual existence," he says, "is identical with the knowledge of that thing." Again—"The possible existence of a thing is identical with the possibility in us of perceiving or knowing it." Thus, until a thing is perceived or known, it can only be said to have a potential or possible existence. And from this a doctrine very similar to that of Ferrier might be deduced, that "nothing exists except plus me"—that is to say, in relation to some mind perceiving it. Aris-
