Plato, Legg. xii. p. 950 B. Χρὴ δὲ οὔποτε περὶ σμικροῦ ποιεῖσθαι τὸ δοκεῖν ἀγαθοὺς εἶναι τοῖς ἄλλοις ἢ μὴ δοκεῖν· οὐ γὰρ ὅσον οὐσίας ἀρετῆς ἀπεσφαλμένοι τυγχάνουσιν οἱ πολλοί, τοσοῦτον καὶ τοῦ κρίνειν τοὺς ἄλλους οἱ πονηροὶ καὶ ἄχρηστοι, θεῖον δέ τι καὶ εὔστοχόν ἐστι καὶ τοῖς κακοῖς. ὥστε πάμπολλοι καὶ τῶν σφόδρα κακῶν εὖ τοῖς λόγοις καὶ ταῖς δόξαις διαιροῦνται τοὺς ἀμείνους τῶν ἀνθρώπων καὶ τοὺς χείρους. Διὸ καλὸν ταῖς πολλαῖς πόλεσι τὸ παρακέλευσμά ἐστι, προτιμᾷν τὴν εὐδοξίαν πρὸς τῶν πολλῶν· τὸ μὲν γὰρ ὀρθότατον καὶ μέγιστον, ὄντα ἀγαθὸν ἀληθῶς οὕτω τὸν εὔδοξον βίον θηρεύειν — χωρὶς δὲ μηδαμῶς, τόν γε τέλεον ἄνδρα ἐσόμενον.
The fathers of families, whose doctrine Plato censures, adopted this doctrine of reciprocity, and built upon it their exhortations to their children. “Be just to others: without that condition, you cannot expect that they will be just to you.” Plato objects to their doctrine, on the ground, that it assumed justice to be onerous to the agent, and therefore indirectly encouraged the evading of the onerous preliminary condition, for the purpose of extorting or stealing the valuable consequent without earning it fairly. Persons acting thus unjustly would efface reciprocity by taking away the antecedent. Now Plato, in correcting them, sets up a counter-doctrine which effaces reciprocity by removing the consequent. His counter-doctrine promises me that if I am just towards others, I shall be happy in and through that single circumstance; and that I ought not to care whether they behave justly or unjustly towards me. Reciprocity thus disappears. The authoritative terms right and obligation lose all their specific meaning.
Plato’s own theory, respecting the genesis of society, is based on reciprocity.
In thus eliminating reciprocity — in affirming that the performance of justice is not an onerous duty, but in itself happiness-giving, to the just agent — Plato contradicts his own theory respecting the genesis and foundation of society. What is the explanation which he himself gives (in this very Republic) of the primary origin of a city? It arises (he says) from the fact, that each individual among us is not self-sufficing, but full of wants. All having many wants, each takes to himself others as partners and auxiliaries to supply them: thus grows up the aggregation called a city.[26] Each man gives to another, and receives from another, in the belief that it will be better for him to do so. It is found most advantageous to all, that each man shall devote himself exclusively to one mode of production, and shall exchange his produce with that of others. Such interchange of productions and services is the generating motive which brings about civic communion.[27] Justice and injustice will be found in certain modes of carrying on this useful interchange between each man and the rest.[28]
[26] Plato, Republic, ii. p. 369 B-C. γίγνεται πόλις, ἐπειδὴ τυγχάνει ἡμῶν ἕκαστος οὐκ αὐτάρκης ἀλλὰ πολλῶν ἐνδεής … μεταδίδωσι δὴ ἄλλος ἄλλῳ, εἴ τι μεταδίδωσιν, ἢ μεταλαμβάνει, οἰόμενος αὑτῷ ἄμεινον εἶναι … ποιήσει δὲ αὐτὴν (τὴν πόλιν), ὡς ἔοικεν, ἢ ἡμετέρα χρεία.
[27] Plato, Republic, ii. pp. 371 B. Τί δὲ δή; ἐν αὐτῇ τῇ πόλει πῶς ἀλλήλοις μεταδώσουσιν ὧν ἂν ἕκαστοι ἐργάζωνται; ὧν δὴ ἕνεκα καὶ κοινωνίαν ποιησάμενοι πόλιν ᾠκίσαμεν.
[28] Plato, Republ. ii. pp. 371 E-372 A. Ποῦ οὖν ἄν ποτε ἐν αὐτῇ (τῇ πόλει) εἴη ἥ τε δικαιοσύνη καὶ ἡ ἀδικία; … Ἐγὼ οὐκ ἑννοῶ, εἰ μή που ἐν αὐτῶν τούτων χρείᾳ τινὶ τῇ πρὸς ἀλλήλους.
Here Plato expressly declares the principle of reciprocity to be the fundamental cause which generates and sustains the communion called the city. No man suffices to himself: every man has wants which require supply from others: every man can contribute something to supply the wants of others. Justice or injustice have place, according as this reciprocal service is carried out in one manner or another. Each man labours to supply the wants of others as well as his own.
This is the primitive, constant, indispensable, bond whereby society is brought and held together. Doubtless it is not the only bond, nor does Plato say that it is. There are other auxiliary social principles besides, of great value and importance: but they presuppose and are built upon the fundamental principle — reciprocity of need and service — which remains when we reduce society to its lowest terms; and which is not the less real as underlying groundwork, though it is seldom enunciated separately, but appears overlaid, disguised, and adorned, by numerous additions and refinements. Plato correctly announces the reciprocity of need and service as one indivisible, though complex fact, when looked at with reference to the social communion. Neither of the two parts of that fact, without the other part, would serve as adequate groundwork. Each man must act, not for himself alone, but for others also: he must keep in view the requirements of others, to a certain extent, as well as his own. In his purposes and scheme of life, the two must be steadily combined.
Antithesis and correlation of obligation and right. Necessity of keeping the two ideas together, as the basis of any theory respecting society.