Dialectic relations are leading principle of Plato's thinking, in the sense of opposing or differing forces leading to another outcome. The mingling of opposites leads to a third outcome: Creations; in all their variations. Infinity and finiteness are the first two classes; then comes the third class of temporal result -- which is only possible through a fourth class of causality. Abstract concepts like hot and cold or wisdom and pleasure, but also high and low tones, are infinite concepts. They are limited by finite concepts, such as measures and degrees: 30 Celsius, but also bigger than, higher than; therefore, temporary states of being. Grammar and linguistics belong, like other human knowledge, to the infinite realm, because its system is self-existing. Other examples are tones, and concepts like hot and cold. This leads to something else: A result, in form of an individual creation with certain qualities. It owes these qualities to a fourth class, namely the cause of its mixture and generation.
Socrates’ and Plato’s philosophy stood at a psychologically high level of describing emotions, desires and thoughts that accompany events in the universe and individual creatures. They made a difference between either observation, or moral judgement, leading to knowledge, emotion or opinion. An erroneous opinion is not necessarily the same as an immoral one, as it doesn’t have the same cause: Respectively observation and memory, versus valued appreciation. Plato did not consider physical causes of pain. He restricted his research to psychological logic.
An example of dialectic dialogue, is this dialogue between Socrate and Protarchus, written in the Dialogue with Philebus. The dialogue mentions topics that are important in Ancient Greece; they often return in Greek philosophy.
Dialectics between infinite and finite, pleasure and wisdom:
"Socrate said in a dialogue with a young man named Philebus, and Protarchus: ‘The sound which passes through the lips, whether of an individual or of all men, is one, and yet infinite. And yet, not by knowing either that sound is one or that sound is infinite, are we perfect in the art of speech; but the knowledge of the number and nature of sounds is what makes a man a grammarian. And the knowledge which makes a man a musician, is of the same kind. Sound is one in music as well as in grammar. But, when you have learned which sounds are high and what low, and the number and nature of the intervals and their limits or proportions, and the systems compounded out of them, which our fathers discovered, and have handed down to us who are their descendants under the name of harmonies; and the affections corresponding to them in the movements of the human body, which when measured by numbers ought, as they say, to be called rhythms and measures; and they tell us that the same principle should be applied to every one and many. When I say, you have learned all this, then, my dear friend, you are perfect; and you may be said to understand any other subject, when you have a similar grasp of it. But, the infinity of kinds and the infinity of individuals, which there is in each of them, when not classified, creates in every one of us a state of infinite ignorance; and he who never looks for number in anything, will not himself be looked for in the number of famous men. Some god or divine man, who in the Egyptian legend is said to have been Theuth, observing that the human voice was infinite, first distinguished in this infinity a certain number of vowels, and then other letters which had sound, but were not pure vowels (i.e., the semivowels); these too, exist in a definite number; and lastly, he distinguished a third class of letters which we now call mutes, without voice and without sound, and divided these, and likewise, the two other classes of vowels and semivowels, into the individual sounds, told the number of them, and gave to each and all of them the name of letters; and observing that none of us could learn any one of them and not learn them all, and in consideration of this common bond, which in a manner united them, he assigned to them all a single art, and this he called the art of grammar or letters.’
Protarchus answered: ‘That seems to be very near the truth, Socrate. Happy would the wise man be, if he knew all things, and the next best thing for him is that he should know himself. Why do I say so at this moment? I will tell you. You, Socrate, have granted us this opportunity of conversing with you, and are ready to assist us in determining what is the best of human goods. For when Philebus said that pleasure, delight, enjoyment, and the like, were the chief good, you answered -- No, not those, but another class of goods. And we are constantly reminding ourselves of what you said, and very properly, in order that we may not forget to examine and compare the two. And these goods, which in your opinion are to be designated as superior to pleasure, and are the true objects of pursuit, are mind and knowledge and understanding and art and the like. There was a dispute about which were the best, and we playfully threatened that you should not be allowed to go home until the question was settled; and you agreed, and placed yourself at our disposal. And now, as children say, what has been fairly given cannot be taken back; cease then to fight against us in this way.’
Socrate answered to that: ‘I remember to have heard long ago certain discussions about pleasure and wisdom, whether awake or in a dream I cannot tell; they were to the effect that neither the one nor the other of them was the good, but some third thing, which was different from them, and better than either. If this be clearly established, then pleasure will lose the victory, for the good will cease to be identified with her:-Am I not right? And there will cease to be any need of distinguishing the kinds of pleasures, as I am inclined to think, but this will appear more clearly as we proceed.’ Soc. ‘Is the good perfect or imperfect?’ Pro.: ‘The most perfect, Socrates, of all things.’ Soc: ‘And is the good sufficient?’ Pro: ‘Yes, certainly, and in a degree surpassing all other things.’ Soc: ‘And no one can deny that all percipient beings desire and hunt after good, and are eager to catch and have the good about them, and care not for the attainment of anything which its not accompanied by good. Let there be no wisdom in the life of pleasure, nor any pleasure in the life of wisdom, for if either of them is the chief good, it cannot be supposed to want anything, but if either is shown to want anything, then it cannot really be the chief good. Reflect; would you not want wisdom and intelligence and forethought, and similar qualities? would you not at any rate want sight? But if you had neither mind, nor memory, nor knowledge, nor true opinion, you would in the first place be utterly ignorant of whether you were pleased or not, because you would be entirely devoid of intelligence. Soc. Let us divide all existing things into two, or rather, if you do not object, into three classes.Were we not saying that God revealed a finite element of existence, and also an infinite? I say that a fourth class is still wanted. Find the cause of the third or compound, and add this as a fourth class to the three others. I want to know whether such things as appear to us to admit of more or less, or are denoted by the words “exceedingly,” “gently,” “extremely,” and the like, may not be referred to the class of the infinite, which is their unity, for, as was asserted in the previous argument, all things that were divided and dispersed should be brought together, and have the mark or seal of some one nature, if possible, set upon them-do you remember?’ Pro: ‘Yes’. Soc: ‘And all things which do not admit of more or less, but admit their opposites, that is to say, first of all, equality, and the equal, or again, the double, or any other ratio of number and measure-all these may, I think, be rightly reckoned by us in the class of the limited or finite; what do you say?’ Soc: ‘The class of the finite which we ought to have brought together as we did the infinite; but, perhaps, it will come to the same thing if we do so now;-when the two are combined, a third will appear.’ Pro: ‘What do you mean by the class of the finite?’ Soc: ‘The class of the equal and the double, and any class which puts an end to difference and opposition, and by introducing number creates harmony and proportion among the different elements.’ Pro: ‘I understand; you seem to me to mean that the various opposites, when you mingle with them the class of the finite, takes certain forms.’ Pro: ‘Yes, I think that I understand you: you mean to say that the infinite is one class, and that the finite is a second class of existences; but what you would make the third I am not so certain.’ Soc: ‘That is because the amazing variety of the third class is too much for you, my dear friend; but there was not this difficulty with the infinite, which also comprehended many classes, for all of them were sealed with the note of more and less, and therefore appeared one.’ Soc: ‘Yes, indeed; and when I speak of the third class, understand me to mean any offspring of these, being a birth into true being, effected by the measure which the limit introduces.’ Soc: ‘Still there was, as we said, a fourth class to be investigated, and you must assist in the investigation; for does not everything which comes into being, of necessity come into being through a cause? Then the first I will call the infinite or unlimited, and the second the finite or limited; then follows the third, an essence compound and generated; and I do not think that I shall be far wrong in speaking of the cause of mixture and generation as the fourth. And therefore the infinite cannot be that element which imparts to pleasure some degree of good. But now-admitting, if you like, that pleasure is of the nature of the infinite-in which of the aforesaid classes, O Protarchus and Philebus, can we without irreverence place wisdom and knowledge and mind? And let us be careful, for I think that the danger will be very serious if we err on this point. … when I asked the question to what class mind and knowledge belong? Yet the answer is easy, since all philosophers assert with one voice that mind is the king of heaven and earth-in reality they are magnifying themselves. And perhaps they are right. But still I should like to consider the class of mind, if you do not object, a little more fully. Let us begin by asking a question. Whether all this which they call the universe is left to the guidance of unreason and chance medley, or, on the contrary, as our fathers have declared, ordered and governed by a marvellous intelligence and wisdom.’ Pro: ‘Wide asunder are the two assertions, illustrious Socrates, for that which you were just now saying to me appears to be blasphemy; but the other assertion, that mind orders all things, is worthy of the aspect of the world, and of the sun, and of the moon, and of the stars and of the whole circle of the heavens; and never will I say or think otherwise.’ Soc: ‘Shall we then agree with them of old time in maintaining this doctrine-not merely reasserting the notions of others, without risk to ourselves,-but shall we share in the danger, and take our part of the reproach which will await us, when an ingenious individual declares that all is disorder?’ Pro: ‘That would certainly be my wish.’ Soc: ‘We see that the elements which enter into the nature of the bodies of all animals, fire, water, air, and, as the storm-tossed sailor cries, “land” [i.e., earth], reappear in the constitution of the world.’ Soc: ‘Only a small fraction of any one of them exists in us, and that of a mean sort, and not in any way pure, or having any power worthy of its nature. One instance will prove this of all of them; there is fire within us, and in the universe’. Pro: ‘True’. Soc: ‘And is not our fire small and weak and mean? But the fire in the universe is wonderful in quantity and beauty, and in every power that fire has’. Pro: ‘Most true’. Soc: ‘And is the fire in the universe nourished and generated and ruled by the fire in us, or is the fire in you and me, and in other animals, dependent on the universal fire?’ Pro: ‘That is a question which does not deserve an answer’. Soc: ‘But is our body nourished wholly by this body, or is this body nourished by our body, thence deriving and having the qualities of which we were just now speaking?’ Pro: ‘That again, Socrates, is a question which does not deserve to be asked’. Soc: ‘And whence comes that soul, my dear Protarchus, unless the body of the universe, which contains elements like those in our bodies but in every way fairer, had also a soul? Can there be another source?’ Pro: ‘Clearly, Socrates, that is the only source.’ Soc: ‘Why, yes, Protarchus; for surely we cannot imagine that of the four classes, the finite, the infinite, the composition of the two, and the cause, the fourth, which enters into all things, giving to our bodies souls, and the art of self-management, and of healing disease, and operating in other ways to heal and organize, having too all the attributes of wisdom;-we cannot, I say, imagine that whereas the self-same elements exist, both in the entire heaven and in great provinces of the heaven, only fairer and purer, this last should not also in that higher sphere have designed the noblest and fairest things?’ Pro: ‘Such a supposition is quite unreasonable.’ Soc: ‘Then if this be denied, should we not be wise in adopting the other view and maintaining that there is in the universe a mighty infinite and an adequate limit, of which we have often spoken, as well as a presiding cause of no mean power, which orders and arranges years and seasons and months, and may be justly called wisdom and mind?’ Pro: ‘Most justly.’ Soc: ‘And wisdom and mind cannot exist without soul?’ Pro: ‘Certainly not.’ Soc: ‘And in the divine nature of Zeus would you not say that there is the soul and mind of a king, because there is in him the power of the cause? And other gods have other attributes, by which they are pleased to be called.’ Pro: ‘Very true.’ Soc: ‘Do not then suppose that these words are rashly spoken by us, O Protarchus, for they are in harmony with the testimony of those who said of old time that mind rules the universe.’ Pro: ‘True.’ Soc: ‘And they furnish an answer to my enquiry; for they imply that mind is the parent of that class of the four which we called the cause of all; and I think that you now have my answer. And let us remember, too, of both of them, (1) that mind was akin to the cause and of this family; and (2) that pleasure is infinite and belongs to the class which neither has, nor ever will have in itself, a beginning, middle, or end of its own.’ Soc: ‘I wonder whether you would agree with me about the origin of pleasure and pain.’ Pro: ‘What do you mean?’ Soc: ‘I mean to say that their natural seat is in the mixed class. … I say that when the harmony in animals is dissolved, there is also a dissolution of nature and a generation of pain. And the restoration of harmony and return to nature is the source of pleasure, if I may be allowed to speak in the fewest and shortest words about matters of the greatest moment. Let us next assume that in the soul herself there is an antecedent hope of pleasure which is sweet and refreshing, and an expectation of pain, fearful and anxious.’ Pro: ‘Yes; this is another class of pleasures and pains, which is of the soul only, apart from the body, and is produced by expectation.’ Soc: ‘If I remember rightly, when the lives were compared, no degree of pleasure, whether great or small, was thought to be necessary to him who chose the life of thought and wisdom.’ Pro: ‘If so, the gods, at any rate, cannot be supposed to have either joy or sorrow.’ Soc: ‘Certainly not-there would be a great impropriety in the assumption of either alternative. But whether the gods are or are not indifferent to pleasure is a point which may be considered hereafter if in any way relevant to the argument, and whatever is the conclusion we will place it to the account of mind in her contest for the second place, should she have to resign the first. The other class of pleasures, which as we were saying is purely mental, is entirely derived from memory. Let us imagine affections of the body which are extinguished before they reach the soul, and leave her unaffected; and again, other affections which vibrate through both soul and body, and impart a shock to both and to each of them. When I say oblivious, do not suppose that I mean forgetfulness in a literal sense; for forgetfulness is the exit of memory, which in this case has not yet entered; and to speak of the loss of that which is not yet in existence, and never has been, is a contradiction; do you see? Instead of the oblivion of the soul, when you are describing the state in which she is unaffected by the shocks of the body, say unconsciousness. And the union or communion of soul and body in one feeling and motion would be properly called consciousness? And memory may, I think, be rightly described as the preservation of consciousness? And do we not mean by recollection the power which the soul has of recovering, when by herself, some feeling which she experienced when in company with the body? And when she recovers of herself the lost recollection of some consciousness or knowledge, the recovery is termed recollection and reminiscence? I want to attain the plainest possible notion of pleasure and desire, as they exist in the mind only, apart from the body; and the previous analysis helps to show the nature of both. Do we mean anything when we say “a man thirsts”? We mean to say that he “is empty”? Then there must be something in the thirsty man which in some way apprehends replenishment? And that cannot be the body, for the body is supposed to be emptied? The only remaining alternative is that the soul apprehends the replenishment by the help of memory; as is obvious, for what other way can there be?’ Pro: ‘I cannot imagine any other.’ Soc: ‘But do you see the consequence?’ Pro: ‘What is it?’ Soc: ‘That there is no such thing as desire of the body.’ Pro: ‘Why so?’ Soc: ‘Why, because the argument shows that the endeavour of every animal is to the reverse of his bodily state.’ Pro: ‘Yes.’ Soc: ‘And the impulse which leads him to the opposite of what he is experiencing proves that he has a memory of the opposite state.’ Pro: ‘True.’ Soc: ‘And the argument, having proved that memory attracts us towards the objects of desire, proves also that the impulses and the desires and the moving principle in every living being have their origin in the soul. Let me make a further observation; the argument appears to me to imply that there is a kind of life which consists in these affections. I mean when a person is in actual suffering and yet remembers past pleasures which, if they would only return, would relieve him; but as yet he has them not. May we not say of him, that he is in an intermediate state? And has he not the pleasure of memory when he is hoping to be filled, and yet in that he is empty is he not at the same time in pain? But when a man is empty and has no hope of being filled, there will be the double experience of pain. You observed this and inferred that the double experience was the single case possible. Would you say that no one ever seemed to rejoice and yet did not rejoice, or seemed to feel pain and yet did not feel pain, sleeping or waking, mad or lunatic?’ Pro: ‘So we have always held, Socrates.’ Soc: ‘But were you right? Then, how can opinion be both true and false, and pleasure true only, although pleasure and opinion are both equally real? And if rightness attaches to any of them, should we not speak of a right opinion or right pleasure; and in like manner of the reverse of rightness? And if the thing opined be erroneous, might we not say that opinion, being erroneous, is not right or rightly opined? And if we see a pleasure or pain which errs in respect of its object, shall we call that right or good, or by any honourable name? We agree-do we not?-that there is such a thing as false, and also such a thing as true opinion? And pleasure and pain, as I was just now saying, are often consequent upon these upon true and false opinion, I mean. And do not opinion and the endeavour to form an opinion always spring from memory and perception? An object may be often seen at a distance not very clearly, and the seer may want to determine what it is which he sees. He asks himself-“What is that which appears to be standing by the rock under the tree?” This is the question which he may be supposed to put to himself when he sees such an appearance. To which he may guess the right answer, saying as if in a whisper to himself-“It is a man.” Or again, he may be misled, and then he will say-“No, it is a figure made by the shepherds.”‘ Soc: ‘Well, now, I wonder whether, you would agree in my explanation of this phenomenon.’ Pro: ‘What is your explanation?’ Soc: ‘I think that the soul at such times is like a book.’"
Socrate talked with a young man, Phaedrus, about the nature of passionate desire: ‘Every one sees that love is a desire, and we know also that non-lovers desire the beautiful and good. Now in what way is the lover to be distinguished from the non-lover? Let us note that in every one of us there are two guiding and ruling principles which lead us whither they will; one is the natural desire of pleasure, the other is an acquired opinion which aspires after the best; and these two are sometimes in harmony and then again at war, and sometimes the one, sometimes the other conquers. When opinion by the help of reason leads us to the best, the conquering principle is called temperance; but when desire, which is devoid of reason, rules in us and drags us to pleasure, that power of misrule is called excess. Now excess has many names, and many members, and many forms, and any of these forms when very marked gives a name, neither honourable nor creditable, to the bearer of the name. The desire of eating, for example, which gets the better of the higher reason and the other desires, is called gluttony, and he who is possessed by it is called a glutton-I the tyrannical desire of drink, which inclines the possessor of the desire to drink, has a name which is only too obvious, and there can be as little doubt by what name any other appetite of the same family would be called;-it will be the name of that which happens to be eluminant. And now I think that you will perceive the drift of my discourse; but as every spoken word is in a manner plainer than the unspoken, I had better say further that the irrational desire which overcomes the tendency of opinion towards right, and is led away to the enjoyment of beauty, and especially of personal beauty, by the desires which are her own kindred-that supreme desire, I say, which by leading conquers and by the force of passion is reinforced, from this very force, receiving a name, is called love. Consider this, fair youth, and know that in the friendship of the lover there is no real kindness; he has an appetite and wants to feed upon you. As wolves love lambs so lovers love their loves.’ Love is the fourth form of madness, after the ailment, prophetic inspiration and artistic inspiration, which demonstrates not all madness is evil, evil meaning both harmful and immoral. The prophetic gift comes from the divine and is therefor perfect. Prophecy is a glimpse on man’s future as planned by the divine and thus benificial. Another form is madness is a soul being possessed by ‘the Muses’: they ‘inspire a delicate and virgin soul with the frenzy to produce lyrical and other numbers’ which are preserved for posterity. The sane man is no match for the artist consumed by artistic madness, according to Socrate. Love as fourth madness has a harmful and beautifying nature, depending which of the two forces dominate the human soul. Plato pays much attention to the human soul and describes it as a ‘charioteer on a wagon guided by two winged horses, the right one white, healthy, obedient and noble, the left one grey-brown, unhealthy, reddish eyed and rebellious, the more earthy, less ambitious souls loose their wings on the road and stay earthbound in humble abode. These two often clash and struggle and it is up to the charioteer’s mastery which horse prevails. Plato strongly believed in reincarnation of the soul and mentions several periods for good, highly esteemed souls and evil or smaller minded souls.
Sources & further reading:
Works by Plato, The Internet Archive
As we see, exact empirical science on for instance the human body and how it functions has yet to come. However, psychological knowledge -- which is an important field of human knowledge -- flourished at a high level, as did applied artisan mastery, as well as knowledge of the arts. Plato gives detailed descriptions of tones and other aspects of music in his book Politeia. They show, Plato must have had a solid musical education.