But this union must be an orderly and rational union; in other words, it must be one in which Mind is master and Pleasure servant; the finite, the regular, the universal must govern the indefinite, variable, particular. Thus in the perfect life there are four elements; in the body, earth, water, air, fire; in the soul, the finite, the indefinite, the union of the {157} two, and the cause of that union. If this be so, he argues, may we not by analogy argue for a like four-fold order in the universe? There also we find regulative elements, and indefinite elements, and the union of the two. Must there not also be the Great Cause, even Divine Wisdom, ordering and governing all things? The second of the psychological series is the _Parmenides_, in which the great Eleatic philosopher, in company with his disciple Zeno, is imagined instructing the youthful Socrates when the two were on a visit to Athens, which may or may not be historical (see above, p. 34). The most striking portion of this dialogue is the criticism already alluded to of Plato's own theory of Ideas, put into the mouth of Parmenides. Parmenides ascertains from Socrates that he is quite clear about there being Ideas of Justice, Beauty, Goodness, eternally existing, but how about Ideas of such common things as hair, mud, filth, etc.? Socrates is not so sure; to which Parmenides rejoins that as he grows older philosophy will take a surer hold of him, and that he will recognise the same law in small things and in great. But now as to the nature of these Ideas. What, Parmenides asks, is the relation of these, as eternally existing in the mind of God, to the same ideas as possessed by individual men? Does each individual actually _partake_ in the thought of God through {158} the ideas, or are his ideas only _resemblances_ of the eternal? If he partakes, then the eternal ideas are not one but many, as many as the persons who possess them. If his ideas only resemble, then there must be some basis of reference by which the resemblance is established, a _tertium quid_ or third existence resembling both, and so _ad infinitum_. Socrates is puzzled by this, and suggests that perhaps the Ideas are only notions in our minds. But to this it is replied that there is an end in that case of any reality in our ideas. Unless in some way they have a true and causal relation with something beyond our minds, there is an end of mind altogether, and with mind gone everything goes.