While Socrates remained at the good and universal, at implicitly concrete thoughts, without having developed them or having revealed them through development, Plato certainly goes on to the Idea as determined. His defect, however, is that this determinateness and that universality are still outside one another. We should certainly obtain the determinate Idea by reducing the dialectic movement to its result, and that forms an important element in knowledge. Yet when Plato speaks of justice, beauty, goodness, truth, their origin is not revealed; they are not shown as being results, but merely as hypotheses accepted in their immediacy. Consciousness certainly has an innate conviction that they form the highest end, but this their determination is not discovered. Since Plato’s dogmatic expositions of Ideas are lost (supra, p. 11), the dialectic of pure thought is only placed before us by the Dialogues dealing with the subject, and these, just because they deal with pure thought, are amongst the most difficult, viz.: the Sophist, the Philebus, and, more especially, the Parmenides. We here pass over the Dialogues which contain only negative dialectic and Socratic dialogue, because they treat only of concrete ideas and not of dialectic in its higher signification; they leave us unsatisfied, because their ultimate end is only to confuse one’s opinions, or awaken a sense of the necessity for knowledge. But those three express the abstract speculative Idea in its pure Notion. The embracing of the opposites in one, and the expression of this unity, is chiefly lacking in the Parmenides, which has hence, like some other Dialogues, only a negative result. But both in the Sophist and the Philebus Plato expresses the unity also.
a. The fully worked-out and genuine dialectic is, however, contained in the Parmenides—that most famous masterpiece of Platonic dialectic. Parmenides and Zeno are there represented as meeting Socrates in Athens; but the most important part of it is the dialectic which is put in the mouths of Parmenides and Zeno. At the very beginning the nature of this dialectic is given in detail as follows: Plato makes Parmenides praise Socrates thus: “I notice that in conversing with Aristoteles,” (one of those present; it might quite well have been the philosopher, but that he was born sixteen years after Socrates’ death) “you were trying to define in what the nature of the beautiful, just and good, and all such ideas lay. This your endeavour is noble and divine. But train and exercise yourself even more in what the multitude call idle chatter, and look on as useless, as long as you are young, for otherwise the truth will escape you.—In what, Socrates asks, does this exercise consist?—I was much pleased because you said before that we must not be content with contemplating the sensuous and its illusions, but must consider that which thought alone can grasp, and that which alone exists.” I have before[31] remarked that men at all times have believed that the truth could be found through reflection only, for in reflection thought is found, and that which we have before us in the guise of ordinary conception and of belief is transformed into thought. Socrates now replies to Parmenides: “I believed that I should in that way best discern the like and unlike, and the other general determinations in things.” Parmenides replies, “Certainly. But if you begin from a point of view such as that, you must not only consider what follows from such an hypothesis, but also what follows from the opposite of that hypothesis. For example, in the case of the hypothesis ‘the many is,’ you have to consider what will be the consequences of the relation of the many to itself and to the one, and likewise what the consequences of the relation of the one to itself and to the many.” The marvellous fact that meets us in thought when we take determinations such as these by themselves, is that each one is turned round into the opposite of itself. “But again we must consider, if the many is not, as to what will be the result as regards the one and the many, both to themselves and to one another. The same consideration must be employed in respect of identity and non-identity, rest and motion, origination and passing away, and likewise in regard to Being and non-being. We must ask what is each of these in relation to itself, and what is their relation in event of the one or the other being accepted? In exercising yourself fully in this, you will learn to know real truth.”[32] Plato thus lays great stress on the dialectical point of view, which is not the point of view of the merely external, but is a living point of view whose content is formed of pure thoughts only, whose movement consists in their making themselves the other of themselves, and thus showing that only their unity is what is truly justified.
Plato makes Socrates say, as regards the meaning of the unity of the one and many, “If anyone proved to me that I am one and many, it would not surprise me. For since he shows me that I am a many, and points out in me the right and left side, an upper and lower half, a front and back, I partake of the manifold; and again I partake of unity because I am one of us seven. The case is the same with stone, wood, &c. But if anyone, after determining the simple ideas of similarity and dissimilarity, multiplicity, and unity, rest and movement, and so on, were to show that these in their abstract form admit of admixture and separation, I should be very much surprised.”[33] The dialectic of Plato is, however, not to be regarded as complete in every regard. Though his main endeavour is to show that in every determination the opposite is contained, it can still not be said that this is strictly carried out in all his dialectic movements, for there are often external considerations which exercise an influence in his dialectic. For example, Parmenides says: “Are either of the two parts of the one which is—I mean the One and Being—ever wanting to one another? Is the One ever set free from being a part (τοῦ εἶναι μόριον) and Being set free from the one part (τοῦ ἑνὸς μόριου)? Once more, each part thus possesses both the one and Being, and the smallest part still always consists of these two parts.”[34] In other words: “The one is; from this it follows that the one is not synonymous with ‘is,’ and thus the one and ‘is’ are distinguished. There hence is in the proposition ‘the one is’ a distinction; the many is therefore contained in it, and thus even with the one I express the many.” This dialectic is certainly correct, but it is not quite pure, because it begins from this union of two determinations.
The result of the whole investigation in the Parmenides is summarized at the close by saying “that whether the one is or is not, it, as also the many (τἆλλα), in relation to themselves and in relation to one another—all of them both are and are not, appear and do not appear.”[35] This result may seem strange. We are far from accepting, in our ordinary conception of things, quite abstract determinations such as the one, Being, non-being, appearance, rest, movement, &c., as Ideas; but these universals are taken by Plato as Ideas, and this Dialogue thus really contains the pure Platonic doctrine of Ideas. He shows of the one that when it is as well as when it is not, whether like itself or not like itself, both in movement and rest, origination and decay, it both is and is not; or the unity as well as all these pure Ideas, both are and are not, the one is one as much as it is many. In the proposition “the one is,” it is also implied that “the one is not one but many;” and, conversely, “the many is” also indicates that “the many is not many, but one.” They show themselves dialectically and are really the identity with their ‘other’; and this is the truth. An example is given in Becoming: in Becoming Being and non-being are in inseparable unity, and yet they are also present there as distinguished; for Becoming only exists because the one passes into the other.
In this respect, perhaps, the result arrived at in the Parmenides may not satisfy us, since it seems to be negative in character, and not, as the negation of the negation, expressive of true affirmation. Nevertheless, the Neo-platonists, and more especially Proclus, regard the result arrived at in the Parmenides as the true theology, as the true revelation of all the mysteries of the divine essence. And it cannot be regarded as anything else, however little this may at first appear, and though Tiedemann (Platon. Argumenta, p. 340) speaks of these assertions as merely the wild extravagances of the Neo-platonists. In fact, however, we understand by God the absolute essence of things, which even in its simple Notion is the unity and movement of these pure realities, the Ideas of the one and many, &c. The divine essence is the Idea in general, as it is either for sensuous consciousness or for thought. In as far as the divine Idea is the absolute self-reflection, dialectic is nothing more than this activity of self-reflection in itself; the Neo-Platonists regarded this connection as metaphysical only, and have recognized in it their theology, the unfolding of the secrets of the divine essence. But here there appears the double interpretation already remarked upon (p. 19), which has now to be more clearly expounded. It is that God and the essential reality of things may be understood in two different ways. For, on the one hand, when it is said that the essential reality of things is the unity of opposites, it would seem as though only the immediate essence of these immediately objective things were indicated, and as if this doctrine of real essence or ontology were distinguished from the knowledge of God, or theology. These simple realities and their relation and movement seem only to express moments of the objective and not mind, because there is lacking in them one element—that is to say, reflection into themselves—which we demand for the existence of the divine essence. For mind, the truly absolute essence, is not only the simple and immediate, but that which reflects itself into itself, for which in its opposition the unity of itself and of that which is opposed is; but these moments and their movement do not present it as such, for they make their appearance as simple abstractions. On the other hand, they may also be taken to be pure Notions, which pertain purely to reflection into itself. In this case Being is wanting to them, or what we likewise demand for reflection into itself as essential to the divine essence; and then their movement is esteemed an empty round of empty abstractions, which belong only to reflection and have no reality. For the solution of this contradiction we must know the nature of apprehension and knowledge, in order to obtain in the Notion everything there present. Thus shall we have the consciousness that the Notion is in truth neither the immediate only, although it is the simple, nor merely that which reflects itself into itself, the thing of consciousness; for it is of spiritual simplicity, thus really existent—as it is thought turned back on itself, so it is also Being in itself, i.e. objective Being, and consequently all reality. Plato did not state this knowledge of the nature of the Notion so expressly, nor did he say that this essential Being of things is the same as the divine essence. But really it is simply not put into words, for the fact is undoubtedly present, and the only distinction is one of speech as between the mode of the ordinary conception and that of the Notion. On the one hand, this reflection into itself, the spiritual, the Notion, is present in the speculation of Plato; for the unity of the one and many, &c., is just this individuality in difference, this being-turned-back-within-itself in its opposite, this opposite which is implicit; the essential reality of the world is really this movement returning into itself of that which is turned back within itself. But, on the other hand, for this very reason, this being reflected into self—like the God of ordinary conception—still remains with Plato something separated; and in his representation of the Becoming of Nature in the Timæus, God, and the essential reality of things, appear as distinguished.
b. In the Sophist Plato investigated the pure Notions or Ideas of movement and rest, self-identity and other-being, Being and non-being. He here proves, as against Parmenides, that non-being is, and likewise that the simple self-identical partakes of other-being, and unity of multiplicity. He says of the Sophists that they never get beyond non-being, and he also refutes their whole ground-principle, which is non-being, feeling, and the many. Plato has thus so determined the true universal, that he makes it the unity of, for example, the one and many, Being and non-being; but at the same time he has avoided, or it was his endeavour to avoid, the double meaning which lies in our talk of the unity of Being and nothing, &c. For in this expression we emphasize the unity, and then the difference disappears, just as if we merely abstracted from it. Plato tried, however, to preserve the difference likewise. The Sophist is a further development of Being and non-being, both of which are applicable to all things; for because things are different, the one being the other of the other, the determination of the negative is present. First of all, however, Plato expresses in the Sophist a clearer consciousness of Ideas as abstract universalities, and his conviction that this point of view could not endure, because it was opposed to the unity of the Idea with itself. Plato thus first refutes what is sensuous, and then even the Ideas themselves. The first of these points of view is what is later on called materialism, which makes the corporeal alone to be the substantial, admitting nothing to have reality excepting what can be laid hold of by the hand, such as rocks and oaks. “Let us,” says Plato, in the second place, “proceed to the other, to the friends of Ideas.” Their belief is that the substantial is incorporeal, intellectual, and they separate from it the region of Becoming, of change, into which the sensuous falls, while the universal is for itself. These represent Ideas as immovable, and neither active nor passive. Plato asserts, as against this, that movement, life, soul, and thought, cannot be denied to true Being (παντελῶς ὄντι), and that the holy reason (ἄγιον νοῦν) can be nowhere, and in nothing that is unmoved.[36] Plato thus has a clear consciousness of having got further than Parmenides when he says:—
“Keep your mind from this way of inquiry,
For never will you show that non-being is.”
Plato says that Being in anyone partakes both of Being and non-being; but what thus participates is different both from Being and non-being as such.[37]
This dialectic combats two things in particular; and in the first place it is antagonistic to the common dialectic in the ordinary sense, of which we have already spoken. Examples of this false dialectic to which Plato often comes back, are specially frequent amongst the Sophists; yet he did not show sufficiently clearly how they are distinguished from the purely dialectical knowledge which is in the Notion. For example, Plato expressed his dissent when Protagoras and others said that no determination is absolutely certain—that bitter is not objective, for what to one person is bitter, to another is sweet. Similarly, large and small, more and less, &c., are relative, because the large will be, in other circumstances, small, and the small will be great. That is to say, the unity of opposites is present to us in everything we know, but the common way of looking at things, in which the rational does not come to consciousness, always holds the opposites asunder, as though they were simply opposed in a determinate way. As in each thing we demonstrate unity, so do we also show its multiplicity, for it has many parts and qualities. In the Parmenides, Plato, as we saw above (p. 58), objected to this unity of opposites, because it must thereby be said that something is one in quite another respect from that in which it is many. We thus do not here bring these thoughts together, for the conception and the words merely go backwards and forwards from the one to the other; if this passing to and fro is performed with consciousness, it is the empty dialectic which does not really unite the opposites. Of this Plato says, “If anyone thinks he has made a wonderful discovery in ascertaining that he can drag thoughts this way and that, from one determination to another, he may be told that he has done nothing worthy of praise; for in so doing there is nothing excellent or difficult.” The dialectic that annuls a determination because it reveals in it some defect, and then goes on to establish another, is thus wrong. “The point of difficulty, and what we ought to aim at, is to show that what is the other is the same, and what is the same, is another, and likewise in the same regard and from the same point of view to show that the one has in them come into existence if the other determination is revealed within them. But to show that somehow the same is another, and the other also the same, that the great is also small” (e.g. Protagoras’s die), “and the like also unlike, and to delight in thus always proving opposites, is no true inquiry (ἔλενχος), but simply proves that he who uses such arguments is a neophyte,” in thought, “who has just begun to investigate truth. To separate all existences from one another is the crude attempt of an uncultured and unphilosophical mind. To cause everything to fall asunder means the perfect annihilation of all thought, for thought is the union of ideas.”[38] Thus Plato expressly speaks against the dialectic of showing how anything may be refuted from some point of view or another. We see that Plato, in respect of content, expresses nothing excepting what is called indifference in difference, the difference of absolute opposites and their unity. To this speculative knowledge he opposes the ordinary way of thinking, which is positive as well as negative; the former, not bringing the thoughts together, allows first one and then the other to have value in their separation; the latter is, indeed, conscious of a unity, though it is of a superficial, differentiating unity in which the two moments are separate, as standing in different aspects.
The second point against which Plato argues is the dialectic of the Eleatics, and their assertion, which in its nature resembles that of the Sophists, that only Being is, and non-being is not. To the Sophists this means, as Plato puts it: Since the negative is not, but only Being is, there is nothing false; everything existent, everything which is for us, is thus necessarily true, and what is not, we do not know or feel. Plato reproaches the Sophists for thus doing away with the difference between true and false.[39] Having arrived at this stage in the knowledge of the dialectic (and the whole matter is merely a difference of stages) the Sophists could allow what they promise—that everything that the individual, according to his belief, makes his end and interest, is affirmative and right. Hence it cannot be said that such and such an act is wrong, wicked, a crime; for this would be to say that the maxim of the action is wrong. No more can it be said that such and such opinion is deceptive, for in the opinion of the Sophists the proposition implies that what I feel or represent to myself, in as far as it is mine, is an affirmative content, and thus true and right. The proposition in itself seems quite abstract and innocent, but we first notice what is involved in such abstractions when we see them in concrete form. According to this innocent proposition there would be no wickedness and no crime. The Platonic dialectic is essentially different from this kind of dialectic.