"we seem to have been rather philosophically nearsighted, attempting to find justice in the individual man, rather than seeking it at large in the ideal state."
Mmm... nope. Here, Plato is fatally wounded by Sophistry. His body falls flat on its face.
This is the "emergent properties" fallacy. An emergent property is literally a magic ritual. You wave your arms a particular way, chant gibobibol, and, for no physical reason, a stove in Connecticut is fired up. Even literal magic rituals aren't this specious.
If you can't describe an event in terms of its underlying components, then it didn't happen. A just society must be made up of individual just agents, or else there is no such thing as justice. As such, the analysis ought to focus on just individuals, as they are less complicated and thus easier to understand than a society as a whole.
Similarly, a [society] cannot become rich by impoverishing every individual agent. If justice is imprudent for the individual, it will be imprudent for society. Even under extreme conditions, [society] ought to pay for the justice (with what? everyone is poor!) so that the individual just agent sees a net win. if [society] cannot pay for the alleged justice out of the profits of justice, then the individual is losing more than the society is gaining. It's parasitism, directly contrary to justice by inspection.
No, Plato, no. Bad Plato! You're grounded! No soup!
I like to think this is pure Plato, with hardly any real Socrates, since it's so far off topic. However - stop me if you've heard about this - ad hominem is a fallacy. If Socrates really did say it, all it means is Socrates was more confused than I thought.
Summary of Plato's city: we already tried Capitalism and it works better. Price signals >> Plato. If you want things, try buying them rather than mandating them. Mandates are unjust and irresponsible, galaxy brain.
"People unite to form a community because of mutual needs: food, dwelling, the growing of food, and so on."
Not needs. Hermits are a thing. The only need a hermit cannot satisfy is the social need, due to that whole logical contradiction malarky. However, it is dramatically cheaper to specialize and trade rather than attempting to do everything yourself.
"Glaucon objects and says that this is merely a well-fed state, fit only for pigs."
Scholars gonna schol.
Again, matter is not worse than mind. Matter is a special kind of mind.
It is true that frequently a peasant needs a lord to tell them what their more esoteric desires actually mean. However, grass monkeys are in fact characterized by desires beyond food and sleep. A [well-fed state] is a state in which you have a bunch of free time which you can spend pursing more esoteric desires. Wealth is wealth. Trade is possible. This may not occur to peasants without being told, but Glaucon is no peasant, and Manichean mandatory-or-forbidden thinking is beneath him.
"But we do not want them to turn against their fellow citizens. So we may liken their training"
Incentives >> training. Scholar's fallacy. "Ideas matter." Not at this level they don't. Instead Conquest #1 applies. Any ideas you put in their head, except the accurate ones, will rapidly be overwritten. You may have intellectual dominance but that doesn't mean they're completely brainless.
Truth has authority. Fiat vox veritatis, ruat caelum. If you speak the truth, you have authority on account of being Vertias' messenger. No truth, no authority.
Secure your shit. If you don't want them attacking the ingroup, then make that decision irrational. There are numerous ways to arrange this, so you can pick your favourite.
"But some of these stories must be modified, because Homer and the other poets and storytellers often tell us stories in which the gods commit bad acts, crimes, duplicitous homicides."
Plato casually going full Sophist. Arrogance.
Is Plato a better storyteller than Apollo? He is not. See also: Chesterton's fence.
"Since the gods can do no wrong, these old stories must be false"
"In other words, whatever evils beset mankind, they are to be attributed
to causes other than God, because God is the seat of good things only."
Hello there Christianity. I didn't expect to see you around so early.
Theology makes dramatically more sense if you drop the omnipotence assumption. At the very least, even the highest god can't violate logic. Can't exist without existing. Can't draw a triangle with no sides. Can't have the Sun rise at dusk.
"since children often identify with the figures of fiction, they may be liable to emulate the crimes of the gods as related in these false stories"
Did you know Plato thinks videogames cause violence?
Q: "Who was Plato's wife?"
A: "He was not married and did not have a wife."
Don't let gay men tell you what children are like, geniuses.
"The supreme lie is a lie against God"
Remember not to equivocate Plato's God with bearded sky daddy. Plato is ontologically committed to Deism.
Under Deism, all lies are lies about God. God is Creation and Creation is God. If you lie about a thing which exists, it's about God. You can't lie about things that don't exist; the null set can neither confirm nor deny any statements about it.
Of course, Plato, like every Sophist, is lying here.
Plato, at least, we can be sure was a fool. For once, Hanlon's razor applies. Incompetence, not malice. Plato's sodomite disorder was a tragedy, and the co-morbidities are likely responsible for his inability to think in straight lines. When he engages in Sophistry, it's due to his poor constitution weakening his ability to resist Sophist infection, whilst being immersed in Sophist culture.
He was still a φαγγωτ and it's important to reject his φαγγωτry. It is, unfortunately, important to know when some modern is echoing some Platonic fallacy, which means reading (at least a summary of) Plato. Or else becoming a grandmaster logician yourself so you can reliably and efficiently find the error from first principles.