In the Seventh Letter Plato says that concerning each thing that exists there are five aspects we must distinguish: 1/ the thing itself (auto), 2/ the knowledge of it (epistȇmȇ), 3/ its image (eidȏlon), 4/ its definition (logos), 5/ its name (onoma). He brings to light these five aspects on the example of a circle, which makes it clear that ‘the thing itself’ is the Form as we know it from the Republic, the Phaedrus, the Symposium, and the Timaeus. Then he says that ‘the same applies to straight as well as (t’auton dȇ peri te eutheos hama kai) to circular form (peripherous schȇmatos), to colours (kai chroas), to the good (peri te agathou), the beautiful (kai kalou), the just (kai dikaiou), to all bodies whether manufactured (kai peri sȏmatos hapantos skeuastou te) or coming into being in the course of nature (kai kata phusin gegonotos)’, 342d3-6).
Plato’s inclusion of ‘all bodies manufactured’ in the Seventh Letter points to the tenth book of the Republic, where Socrates speaks of the form of bed (klinȇ hȇ en tȇi phusei ousa ‘bed existing in nature’), which is created by God (hȇn theon ergasasthai, 597b5-7). Does it then mean that in his old age Plato fully corroborated the view of the forms as entities created by God, which he adumbrated in Republic X?
Adam notes on Republic X, 597b6-7: ‘hȇn – theon ergasasthai. “Occurrit, ut videtur, quasi ex improviso Platoni, Deum Idearum auctorem appellare [‘It occurs to Plato, as can be seen, as if by improvisation, to call God the creator of Forms’]”, truly enough, in the restricted sense that we ought to lay no stress on this passage by itself as evidence for the origin of the Ideas. But, if God and the Idea of Good are the same, Plato is merely saying in theological language what he formerly said in philosophical, when he derived the ousia [‘being’] of all other Ideas from the Idea of Good (VI 509 B).’ (J. Adam, The Republic of Plato, Cambridge University Press, 1902, digitally printed in 2009, vol. II, p. 390-391.)
In Republic 509 B Plato says: ‘The good not only infuses the power of being known into all things known (tois gignȏskomenois mȇ monon to gignȏskesthai hupo tou agathou pareinai), but also bestows upon them their being and existence (alla kai to einai te kai tȇn ousian hup’ ekeinou autois pareinai), and yet the good is not existence (ouk ousias ontos tou agathou), but lies far beyond it in dignity and power (all eti epekeina tȇs ousias presbeiai kai dunamei huperechontos, 509b6-10, tr. Jowett).’
Is Adam right, when he maintains that Plato in Republic X says in theological language what he formerly, that is in 509b6-10 said in philosophical? In Republic X Socrates goes on to say: ‘God (ho theos), whether from choice or from necessity (eite ouk ebouleto, eite tis anankȇ epȇn) made one bed in nature and one only; two or more such beds neither ever have been nor ever will be made by God (mȇ pleon ȇ mian en tȇi phusei apergasasthai auton klinȇn, houtȏs epoiȇsen mian monon autȇn ekeinȇn ho estin klinȇ; duo de toiautai ȇ pleious oute ephuteuthȇsan hupo tou theou oute mȇ phuȏsin) … Because even if He had made but two (hoti ei duo monas poiȇseien), a third would still appear behind them (palin an mia anaphaneiȇ) of which they again both possessed the form (hȇs ekeinai an au amphoterai to eidos echoien), and that would be the real bed and not the two others (kai eiȇ an ho estin klinȇ ekeinȇ all’ ouch hai duo) … God knew this, I suppose (tauta dȇ oimai eidȏs ho theos), and He desired to be the real maker of a real bed (boulomenos einai ontȏs klinȇs poiȇtȇs ontȏs ousȇs), not a kind of maker of a kind of bed (alla mȇ klinȇs tinos mȇde klinopoios tis), and therefore he created a bed which is essentially and by nature one only (mian phusei autȇn epoiȇsen).’ Can this be seen as a theological version of what Socrates said in Republic VI, 509 B?
In Republic VI 485b2-3 Plato speaks of the Forms as ‘the being that is eternal (tȇs ousias tȇs aei ousȇs), not disturbed by generation and decay (kai mȇ planȏmenȇs hupo geneseȏs kai phthoras’. These are the Forms which Plato introduced in the Phaedrus, not the Forms that God makes (ergasasthai) in Republic X. In the Phaedrus Plato’s Socrates proclaimed that ‘God has his divinity by virtue of being with the Forms’ (pros hoisper theos ȏn theios estin, 249c6)’. In view of this, the Forms could be seen as an ‘introduction of new deities’ – the charge for which Socrates was sentenced to death. Plato as the author of the Phaedrus was protected by the amnesty announced by the victorious democrats after their defeat of the Thirty against any such charge. Since the Forms discussed in Republic V-VII are the Forms introduced in the Phaedrus, Plato had to devise a new protection; this he did by presenting God as the maker of forms in the last book of the Republic. If the Forms in the Republic needed protection against the notion of the Forms as entities from which God derives his divinity announced in the Phaedrus, the Forms in the Seventh Letter needed such protection even more, for in it Plato pointed to the Phaedran notion of the written word as incapable of expressing what he had told Dionysius. This protection Plato devised by pointing to forms of ‘all bodies manufactured’ (peri sȏmatos hapantos skeuastou), which links the Seventh Letter to Republic X with its notion of God as the maker of the form of bed, and putatively of forms as such. But the form of bed of which Socrates speaks in Republic X, form made by God, is a fundamentally different form from the eternal Forms of books V-VII.
What Plato says in Republic VI, 509 B about the Good that bestows upon the Forms being and existence (alla kai to einai te kai tȇn ousian hup’ ekeinou autois pareinai, 509b6-7), can best be viewed in terms of the community of Forms (allȇlȏn koinȏnia) indicated in Republic V, 476a4-7.