ON THE FIRST PART OF PLATO 'S PARMENIDES. 15 no difficulty in admitting that the same predicate can be thought or uttered about any number of different things. In fact the proposed version of the doctrine would bring it very near to Aristotle's view of the requisites of predication ; the Idea would become a ev Kara 7roX,wv instead of a ev Trapa rl vroXXtt. Only, as Parmenides is careful to point out and Aristotle not always anxious to remember, we should have escaped from our difficulty by ignoring it. For the unity of the concept is not psychological but logical ; it is one concept because it has a single reference or meaning not because it is in some unexplained way " one mental state," whatever such a phrase might mean. In Plato's language, the one concept is one in virtue of having one object which is conceived through it ; thus we are brought face to face with the problem, so often neglected by the popular philosophy of all ages, of the relation between truth and reality. The concept, to be valid at all, must have a reference to some- thing which falls outside its own existence as psychical fact, and this something must in some sense be a unity, so that the problem of the Platonic Idea is still with us. The passage of our dialogue is only one of many which show that Plato was aware to an extent to which few philosophers have been so of the impossibility of that " cheap and easy monism " which takes it for granted that logic and reality, truth and immediate fact, can be simply identified without further ado. That an interpretation which would make the unity of a concept lie in its mere existence as a psychical fact should have found favour with modern interpreters of Plato, under the form of an identification of the Ideas with the thoughts of God for instance, is simply not creditable to their own logic. The conclusion of the passage, with its dilemma that if the Idea is a mere concept either all things think or there are unthought thoughts, points out the inevitable consequence which arises from the initial mistake of identifying reality with mere psychical existence as such. It does not, of course, in any way exclude the view that existence as a psychical event is an inseparable aspect of all reality. It is valid against all forms of the doctrine that reality is a mere collection of " states of consciousness," but must not be con- fused with the vulgar " realist " view that there is existence which has no aspect of psychical fact at all. Of the connexion of the argument just examined with the following investigation of the hypothesis that the Idea is a sort of transcendent type which the particular "imitates" I have spoken at length in my previous articles on the Par- menides, and I have nothing in principle to add to the proof
