Republic 6 (502c-511e)

The Sun and the Divided Line

Contents:

• The Eidos of the Good  (502c-509c)

  • The Analogy of the Sun

  • Interpretation of the Analogy of the Sun

  • Why is the Good the most important study of the lover of wisdom?

• The Divided Line  (509d-511e)

• Suggestions for Further Reading

 The Eidos of the Good  (502c-509c)

• Socrates now raises the level of the conversation.

• The philosopher who is best to rule the city must not only know what justice is, for justice is but one specific instance of the good.

• The greatest study of all is the study of the idea ---The Form (Eidos)  of the good---Goodness Itself. (505a)

  • Plato believes that the good which is real (has being) as opposed to that which only seems good is the Feature Itself ---The Form (Eidos)  that is Goodness Itself.

  • Plato believes that specific goods like justice, health, wisdom are good only to the extent that they participate in the Form of Goodness Itself.  ["When an object can be said to be F, it is by virtue of a relation between it and the Form of F (see 475e-476d).  This relation, "participation" usually seems to hold between sensible objects and Forms but it can perhaps also hold between Forms too, e.g. between a Form and the Form of the Good."  Nicholas P. White. A Companion to Plato's Republic, p. 175.]

  • The philosopher cannot know whether a specific good (for example, a good law) is really good or only apparently good, if she does not know what Goodness itself is.  No one is satisfied with the obtainment of the seeming good; everyone seeks the genuine article.

  • Plato assumes that if we do not know the entirely adequate definition of Goodness Itself we cannot know (only opine) that some particular thing is good.  (Those who find this claim highly suspect call the claim the Socratic fallacy).

  • Since the ruler must be able to know what is fine and good among the laws and practices of the City, the ruler must seek knowledge of Goodness Itself.

• Every aspect of the tripartite soul is desirous of some particular Good or End.  Each of those particular goods are good in so far as they participate in Goodness Itself (share the feature of goodness).  Goodness Itself then is the ultimate End of human life---the ultimate fulfillment of all human desiring.

  • Human flourishing, the achievement of excellence as a human being, is possible only when the rational psyche apprehends the Form of the Good.  Only then can it provide itself with the object of its desire---the true Good, and can recognize the Ends of fulfilling the goods of the Spirited and appetitive souls as well.  This commingling and identification of the rational desire for the Good and the object of knowledge: the Form of the Good, is a kind of secular beatitude---a life fulfilling consummation.

• But what is The Good?  (508a-509c)

  • Socrates must distinguish the Form of the Good from the particular goods that participate in it, for example: must distinguish between Goodness Itself and the goodness of (some types) of pleasure or the goodness of prudence.

  • Socrates claims not to have knowledge of the Form of the Good. 

  • However something that is a child of the Good and looks like it can be described.

The Analogy of the Sun

• Socrates suggests that of the many fine and good things, the feature that unites them is the Idea of the Good.  This one idea must be real, for otherwise there would be no particular thing that would be good.

• Between the visible and sight there must be a third thing which allows the visible to come out of the darkness and be seen; and that third thing is light.  The god that supplies light is Apollo, the sun.*

  • *After the 5th Century BC, Apollo, the son of Zeus and Leto, was identified with Helios, the sun god.  Phoebus Apollo, the god of light, was a moral god concerned with prophecy, medicine, music, poetry, archery and various bucolic arts. He was responsible for law, philosophy and the arts.  He, along with Athena, was a patron god of Athens and his Oracle at his shrine in Delphi inspired Socrates to carry out his sacred mission of exposing intellectual fraud wherever he found it.

• Just as the sun provides the light that makes the eye aware of color and the colored thing visible, so too The Good provides the idea (enlightenment) that allows the rational mind to know the Forms of things.  The Good is that whereby we grasp the universal and eternal Features (eide) of particular things.

• Just as the sun, through the emanation of its heat energy and light causes the generation of living things, so too the Good causes the being of the things it makes knowable.

• Just as the sun causes generation but is not itself generation (is eternally beyond generation or corruption), so too The Good is not itself a being like those it causes, is not itself a thing, but is beyond beings.

Interpretation of the Analogy of the Sun

• What is this all about?  This passage is perhaps one of the most obscure and mysterious in all of Plato's writings.  Plato is offering his cryptic answer to life's most fundamental mystery:  why reality?---why is there anything at all?---nothingness would have been so much simpler.  The analogy with the sun god suggests that Plato's explanation for the universe is a move beyond polytheism to a monotheism.  However, the transcendent source of all the beings and all of the forms is not a personal god.  It is a real, transcendent, eternal, unchanging, universal source of existence; but Goodness Itself has no personality (although Glaucon thinks Socrates owes us a narrative on the Father of the sun-god, and Socrates described Apollo as the "child" of the Good.)  That the Form of the Good is the ultimate cause of the Forms makes sense in light of the fact that: 1. Forms make things what they are and thus are the origin of beings, 2. Forms are universal, permanent, eternal and thus more real (and real making) than particular things which are fleeting, changing, hovering between being and non-being.  2. Forms are united by the Good---when we apprehend an apple, we understand it as participating in the universal and eternal Form (Idea) of Appleness Itself---Appleness itself is ideal, it is perfection without flaws, without corruption.  Thus the Good in the apple, Ideal Appleness, allows us to know the thing as an apple.

• Goodness Itself is a good candidate for ultimate reality since it unites all the Forms of things and the apprehension of the good in things is the same as grasping the thing in its essence, making it known to us.

Why is the Good the most important study of the lover of wisdom?

• Reason will not achieve its End---absolute knowledge of the totality of being--- unless it has an appetite (eros) of its own.  The Faustian quest for complete and absolute knowledge must be driven by a yearning. Since every yearning has its proper object, the ultimate cause of reality (which is mysteriously beyond reality, that is, beyond particular beings) must be an object of intellectual desire.  So ultimate Being must also be ultimate Good, the End of all desiring.  The consummation of human life is in knowledge of Goodness Itself.

  • (All of this is a mistake.  It's the mistake of misplaced concretion.  Goodness is a feature or a characterization of things.  As such it cannot be attributed to the mysterious cause of things.  That cause cannot be known in its own nature (if it's indeed an "it" or has a nature).  Any easy ascription of the features of things to it is a falsification of it.  Being is that whereby or in accord with which things are, but ontic descriptions are fallen that is, they're false descriptions derived from features of things and cannot thereby be legitimately ascribed to Being itself.)

 The Divided Line  (509d-511e)

• Once Socrates has divided up the visible natural world (sun lit) and the intelligible invisible world of the Forms (Good sent), he further illustrates the venture of the philosopher's life with the Divided Line.

• A line A-E is divided in unequal measures: AC-CE.  Then each section is divided by an equal amount so that the following proportions are produced:  [AB:BC::CD:DE]::AC:CE

• AC represents the visible world and includes the categories of visible thing CB and the images and shadows AB that emanate from them.  CE represents the intellected world of the Forms including the categories of mathematical entities and scientific Forms (Natures) CD and the Higher Forms of Wisdom, Justice, Courage, Moderation and the Form of the Good DE.

• The line suggests two progressions, one epistemological, another metaphysical. 

• Epistemological progression:  Starting with the minimal evidence of images and first impressions, the young Guardian gains a tenuous grasp of reality through the images of Homer and Hesiod, the poetic content of musical education.  Ordinary perception of the changing particulars (trees, flowers, Spartans, the agora) provides acquaintance with their universal essences without a full grasping or understanding of them.  A child may perceive clearly the flowers in the garden she is skipping through, without a botanist's understanding of what is there.  The child's awareness is one of opinion not knowledge

  • Only on the intellectual level of CD, apprehension of the Forms of mathematics and scientific natures can the Guardian student obtain knowledge.  A circle is an enclosed arc every point along which is equidistant from a central point.  This essence of Circleness applies to the quadrillions of particular circles and wheels that participate in it.  This essence of Circle is eternal, universal, and unchanging.  These Forms (e.g. of the Isosceles triangle) are imperceptible (because they are ideal, universal and eternal) and thus only apprehended by reason alone.  [A visible line is not really a mathematical line, because as the shortest distance between two points, the line has no width.  Mathematical points have no dimensions at all, and so cannot be apprehended by the senses]

  • Finally, ultimate knowledge is knowledge of Forms which are matters of pure intellection, reasoning not from hypotheses, as in the case of the scientific generalizations from particular observations or from the use of visual illustration as in the case of geometrical proofs, but rather purely from the use of reason alone, e.g. understanding the Form of the Good.  Understanding the Higher Forms results from the method of the dialectic which discovers first principles from which conclusions about particulars are deduced.

  • In terms of the progression of knowledge, Plato is saying that knowledge of the higher Forms is comparable to knowledge derived from Math and Science as knowledge of visible things is to knowledge derived from images and shadows, as knowledge of intellectual Forms is to the opinions derived from perception and imagination.  Knowing the Form of the Good then makes knowledge of anything else possible, whereas opinion formed and restricted to political propaganda, popular media and societal conventions guarantees ignorance of the true, the real and the good.

• Metaphysically the line represents a progression from the most ephemeral, changing, multiple unstable and particular to the more enduring, unified, eternal , universal, stable, permanent and ideal.  So from the unreality and derivative nature of shadows, we progress up the scale of reality to the eternal source of being, the Form of the Good. Math and natural Forms are as real compared to the Higher Forms, as shadows are to perceived things as the entities dwelling in the world of opinion are to the intellected Forms in the World of Knowledge.

• The philosopher grasps this great chain of being and accepts the unconventional notion that ideal Forms are real and perceived particulars are not (as real). Because of her  knowledge of the true Good, only the philosopher can apprehend the fine and the good in the laws and practices of the City.

    Suggestions for Further Reading

• Annas, Julia.  "Understanding and the Good:  Sun, Line and Cave."  Plato's Republic:  Critical Essays.  Ed.  Richard Kraut.  Lanham, MD:  Rowman and Littlefield, 1997.  [143-168]
• Benardette, Seth.  Socrates' Second Sailing:  On Plato's Republic.  Chicago: University of Chicago, 1989.  
• Bloom, Allan.  The Republic of Plato.  New York: Harper Collins, 1968.   [139-157]
• Irwin, Terence.  Plato's Ethics.  New York:  Oxford University Press, 1995.  [271-274]
• Pappas, Nickolas.  Plato and the Republic.  New York: Routlege, 1995.  [114-117] 
• Sallis, John. Being and Logos: Reading the Platonic Dialogues.  3rd ed.  Bloomington, IN:  Indiana Univeristy Press, 1996. [396-412]
• White,  Nicholas P.  A Companion to Plato's Republic.  Indianapolis: Hackett, 1979.  [163-182]

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