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The ‘Simile Of Light’ In Plato'S Republic

  • N. R. Murphy (a1)

At the end of Republic VI. Socrates compares the Good with the sun as a cause both of existence and intelligibility. Afterwards, when he continues and expands this comparison, the symbolism becomes so complex that the interpretation of almost every part of it is in dispute. We start with the contrast of light and darkness; to this is next added the contrast of image and original, and also of up and down along a vertical line; in the allegory of the Cave these three sets of contrasted terms are worked in together so as to explain the effect on the soul of the intellectual education by which we are converted from what is dark and imitative and ascend finally to knowledge of the Good.

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page 93 note 1 E.g. Jackson, H. in J.Phil. 1882.

page 94 note 1 A few actual statements from these articles may be considered in order to show the difficulties inherent in this type of interpretation.

(α) ‘The bonds that hold the prisoners fast are devised by men’ (Ferguson, , Classical Quarterly, XVI., p. 16). But surely these bonds are the ‘leaden weights of becoming’ (519a), and all the lower desires and appetites which are no doubt often made heavier bonds than they need be by the work of men, but belong inherently to human nature. In the ideal city these bonds are loosened by the preliminary training in music and gymnastic, by which the soul is prepared to ‘welcome reason when it shall come’ (402a), but they are not removed by this training (522).

(β) ‘The puppets are … apparently valueless to the philosopher’ (loc. cit., p. 24). But in looking at the puppets the released prisoner is said to look at something ‘nearer to reality ’ (513d). How, then, can they be valueless for education, or be treated as the mere shams and sorceries of a Sophist’

(λ) ‘The natural symbolism (outside the Cave) illustrates the Platonic education’ (p. 15). By contrast no ‘Platonic’ education is supposed to be going on within the Cave. But Plato ex pressly tells us (e.g. 532b) that the prisoner's release is effected by mathematics. Professor Ferguson avoids this (p. 24, note 2) by separating the release from the propaideutic as being two successive stages. But how can we reconcile this with the repeated assertions in Book VII that the means of conversion is the mathematical propaideutic? Mathematics must begin in the Cave in order to rescue us from it. Any other interpretation would run counter to the whole trend of Book VII., for the metaphors of turning round and leading upwards, started in the Cave, are carried on throughout the book and explained in non-metaphorical terms.

page 96 note 1 (i) Firelit images; (ii) the puppets which are the immediate originals of these images; (iii) the originals of the puppets outside the Cave first seen in shadow then reflected in water; this grade as a whole is called Beta. θεῖα φαντάνματα (iv) these originals themselves, etc. A comparison of 532a and b with 516 enables us to distinguish these groups without difficulty; the complexity of the last two groups accords well enough with the description of the sciences in Book VII., arranged as they are according to the increasing complication of their subject-matter. For the (probable) complexity of dia lectic see 532e 1.

page 96 note 1 There is perhaps some natural reluctance (urged very strongly by Professor Ferguson) to accept ‘looking at puppets’ as a symbol for mathematical instructedness, since puppets connote artificiality and pretence. But Plato's statement in 515d is quite explicit–πρς μλλον ντα τετραμμένος ρθτερον βλέποι

page 97 note 1 It is curious that even after the reference to mathematics in the Line Glaucon does not seem to suspect that mathematics is the science required ð ζητομεν μάθημα to makethe bridge between the material and the ideal world, and has to be argued into the recognition of this possibility by a long discussion.

page 98 note 1 This point is brought out very clearly by ProfessorStocks, J. L. in Classical Quarterly, Vol. V., 1911, on the ‘Divided Line’.

page 98 note 2 Expressed in allegorical terms this wouldbecome ‘from contemplation of objects lit by the fire underground, whether shadows or puppets, to contemplation of θεῖα ϕαντάσματα in the sunlight.’

page 99 note 1 If Plato conceived the segments as unequal, according to the usual texts (509a 6), this adds a metaphorical element of which no use is made in the Cave, although it could easily have been included by indicating the relative length of the stages in the πάνοôος. It is true that in 514 the entrance to the cave is called μακρά and the fire said to be πόρρωθεν, and Proclus seems to think that there is some counterpart in the Cave to the inequality of length of the segments, but the length of the entrance to the cave is apparently insisted on by Plato only to avoid having the sun shining directly into it, and there seems to be really no counterpart in the Cave to this feature in the Line. Therefore, although the point is not of great importance, the following objections to the usual reading may be made:

(i) It does not seem that the authority of any existing manuscript on this point can be called decisive. As Stallbaum says, ‘antiquam fuisse litem de hac lectionis diuersitate ex Schol. ad hunc locum patet.’

(ii) It is not necessary to think of the segments as unequal in order to see the force of Plato's ratios. The ratios are in all cases drawn between what fill the segments, and it is not necessary to think of the diagram as having a corresponding shape. Some translations imply ratios between the segments of the diagram itself, but a close reading of the Greek will not confirm this.

(iii) Plato nowhere refers to any of the segments as the ‘longer’ or the ‘shorter’ segment, but only as the upper or lower. So we do not even know which he thought of as the longer. ‘Plutarch’ thinks the lower because it containsthe many, while the upper contains the one; Proclus thinks the upper because it is κρεῖττον κα περιέχον θἄτερον. It is generally assumed the latter is right, but we can only conjecture.

(iv) This inequality of length would be the only explanatory element not gathered up again into the Cave.

It might be worth while, therefore, since the more usual emendations, such as άν' ισα etc., are unsatisfactory, to suggest that a plausible text could be obtained by deleting the words ἂνισα τμήματα altogether as a gloss. By the time of Euclid's Elements (e.g. I. 10) δίχα τέμνειν is an established technical term meaning to ‘bisect’ (into equal parts, of course) and requires for Euclid no further qualification such as εíσ ισα. I can find no evidence as to the mathematical usage in Plato's time, but it does not seem impossible that Plato should have been using δίχα τέμνειν in this sense, nor that someone should have misunderstood the usage, felt doubt about the following ν τძν αὐτν λγον, and explained it by a marginal gloss ἂνισα τμήματα, which afterwards crept into the text. The effect of conceiving the segments as equal would be to enable us simply to disregard their relative lengths. The Line would merely have four compartments one above the other without any significant shape.

There is obviously, however, a good deal of conjecture here, and if the text is sound (and the only serious objection I have against it is the discrepancy with the Cave), it must be admitted that this inequality of length is an element of metaphor, a contrast of short and long, in the Line which disappears in the Cave.

page 120 note 1 Perhaps the term ‘illustrative’ still requires some explanation. The division of visibles into image and original is not illustrative in the same sense as their division into dark and bright. The latter is purely illustrative, since brightness does not strictly apply to, but only stands for, the superior intelligibility of εἲδη) which are not in fact either bright or dark. But μίμησις and its correlatives apply, for Plato, equally well at any level; even if he is not entirely satisfied with them, there is no term which he prefers to them as a description of the relationship between εἲδη and τ πολλά. In calling the lower subdivision ‘illustrative,’ therefore, what is meant is that Plato is not seriously concerned at the moment (as he is, e.g., in Book X.) with the internal grading of the phenomenal world. If I am right in arguing that the Line is meant to prepare for the Cave rather than to supply separate and additional information about the Good, then the ultimate purpose of the lower subdivision is to provide a basis of comparison for παιδεία and παιδενσία. παιδενσία is comparable to εἰκασία, παιδεία to πίστις so also with the two stages παιδεία. The distinction of εἰκόνες and ζῷα is metaphysically valid, but they together with είκασία and πίστις belong to a purely visual experience within which the problems about apparent and real good which Plato is dealing with do not tend to arise. His general argument is that the distinction of appearance from reality applies as definitely in the pursuit of good as in theory; but he does not here point out the superior reality of visible solids in order to convict the unphilosophical of mistaking shadow for substance in their daily concerns (as no doubt he might have done), but to convict them, by analogy, of mistaking phenomenal for real in his usual sense of reality. I understand the whole set of similes as a comparison of παιδεία with παιδενσία in their effects on the practical life, and the view which I am arguing against is that Plato has any intention here of recognizing a better and a worse within παιδενσία. The references to honours and rewards within the Cave in 516c is clearly contemptuous, for the philosopher judges merit by other standards.

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The Classical Quarterly
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