ON PLATO'S PHAEDO. 369 are, in Aristotelian phrase, the matter of which it is the form. But the same tune, i.e., the same combination of notes may be played on many instruments; and so the analogy would not prove the mortality of the soul, unless the soul be, as in Aristotle's view, the form or realisation of the body. If the body be analogous to the notes of the tune, the soul perishes with the body ; if the body be analogous to the musical instrument, it need not. It may seem strange that Plato should not have noticed this way of turning aside the objection. Perhaps the whole harmony-theory seemed to him to deny too much the essential unity of the soul. 3. We can now pass to the third great argument, to which all the others lead up, that which makes the question of the soul's immortality expressly and directly depend on the doctrine of Ideas. It is impossible here to go through the complicated and difficult details of the argument. The difficulties are partly matters of interpretation of language and must be left to the philologer ; partly they depend on the whole problem raised by the different forms in which the theory of ideas appears in Plato. We are at a loss to know how far we may take as a guide the presentation of the theory in other dialogues. 1 The main argument in its briefest form is this : The soul partaking in, or manifesting in itself, the idea of life cannot partake in the opposite idea, that of death, just as fire which partakes in the idea of heat cannot admit the idea of cold, and as the abstract number three, which is odd, cannot admit the idea of even. Cold fire, even three, dead soul would imply cold heat, even odd, dead life, and so involve a contradiction in terms. What, according to Plato, is the relation of the soul to the ideas ? Teichmuller argues that, because the soul is not an idea, and because in Plato's system only the ideas really exist, therefore soul does not exist. That the particular soul does not exist in the same way as the ideas we may agree. But (1) it may be doubted whether Plato and his critic are using ' existence ' (being) in the same sense. As Lotze has very well pointed out (Logic, Eng. Tr., p. 440), when Plato speaks of the ideas as ra 6Vr&><? ovra he really means that they are alone valid, not that they are existent things ; but the 1 The questions of interpretation will be found most carefully discussed in Mr. Archer-Hind's edition. May I here, once for all, acknowledge the obligation under which every student of Plato must stand to him ? The points of disagreement in this paper must be taken as presupposing this obligation. The latest important contribution to the study of the ideal theory has been made by another Cambridge Scholar, Mr. H. Jackson, in the Journal of Philology, vols. x.-xiii. 25
