Views of critics about this contradiction.
The subject evidently presented itself to Plato in two different ways at different times. Which of the two is earliest, we have no means of deciding. The commentators, who favour generally the view taken in the Gorgias, treat the Protagoras as a juvenile and erroneous production: sometimes, with still less reason, they represent Sokrates as arguing in that dialogue, from the principles of his opponents, not from his own. For my part, without knowing whether the Protagoras or the Gorgias is the earliest, I think the Protagoras an equally finished composition, and I consider that the views which Sokrates is made to propound in it, respecting pleasure and good, are decidedly nearer to the truth.
Comparison and appreciation of the reasoning of Sokrates in both dialogues.
That in the list of pleasures there are some which it is proper to avoid, — and in the list of pains, some which it is proper to accept or invite — is a doctrine maintained by Sokrates alike in both the dialogues. Why? Because some pleasures are good, others bad: some pains bad, others good — says Sokrates in the Gorgias. The same too is said by Sokrates in the Protagoras; but then, he there explains what he means by the appellation. All pleasure (he there says), so far as it goes, is good — all pain is bad. But there are some pleasures which cannot be enjoyed without debarring us from greater pleasures or entailing upon us greater pains: on that ground therefore, such pleasures are bad. So again, there are some pains, the suffering of which is a condition indispensable to our escaping greater pains, or to our enjoying greater pleasures: such pains therefore are good. Thus this apparent exception does not really contradict, but confirms, the general doctrine — That there is no good but the pleasurable, and the elimination of pain — and no evil except the painful, or the privation of pleasure. Good and evil have no reference except to pleasures and pains; but the terms imply, in each particular case, an estimate and comparison of future pleasurable and painful consequences, and express the result of such comparison. “You call enjoyment itself evil” (says Sokrates in the Protagoras),[75] “when it deprives us of greater pleasures or entails upon us greater pains. If you have any other ground, or look to any other end, in calling it evil, you may tell us what that end is; but you will not be able to tell us. So too, you say that pain is a good, when it relieves us from greater pains, or when it is necessary as the antecedent cause of greater pleasures. If you have any other end in view, when you call pain good, you may tell us what that end is; but you will not be able to tell us.”[76]
[75] Plato, Protagoras, p. 354 D. ἐπεί, εἰ κατ’ ἄλλο τι αὐτὸ τὸ χαίρειν κακὸν καλεῖτε καὶ εἰς ἄλλο τι τέλος ἀποβλέψαντες, ἔχοιτε ἂν καὶ ἡμῖν εἰπεῖν· ἀλλ’ οὐχ ἕξετε.… ἐπεὶ εἰ πρὸς ἄλλο τι τέλος ἀποβλέπετε, ὅταν καλῆτε αὐτὸ τὸ λυπεῖσθαι ἀγαθόν, ἢ πρὸς ὃ ἐγὼ λέγω, ἔχετε ἡμῖν εἰπειν· ἀλλ’ οὐχ ἕξετε.
[76] In a remarkable passage of the De Legibus, Plato denies all essential distinction between Good and Pleasure, and all reality of Good apart from Pleasure (Legg. ii. pp. 662-663). εἰ δ’ αὖ τὸν δικαιότατον εὐδαιμονέστατον ἀποφαίνοιτο βίον εἶναι, ζητοῖ που πᾶς ἂν ὁ ἀκούων, οἶμαι, τί ποτ’ ἐν αὐτῷ τὸ τῆς ἡδονῆς κρεῖττον ἀγαθόν τε καὶ καλὸν ὁ νόμος ἐνὸν ἐπαινεῖ; τί γὰρ δὴ δικαίῳ χωριζόμενον ἡδονῆς ἀγαθὸν ἂν γένοιτο;
Plato goes on to argue as follows: Even though it were not true, as I affirm it to be, that the life of justice is a life of pleasure, and the life of injustice a life of pain — still the law-giver must proclaim this proposition as a useful falsehood, and compel every one to chime in with it. Otherwise the youth will have no motive to just conduct. For no one will willingly consent to obey any recommendation from which he does not expect more pleasure than pain; οὐδεὶς γὰρ ἂν ἕκων ἔθελοι πείθεσθαι πράττειν τοῦτο ὅ, τῳ μὴ τὸ χαίρειν τοῦ λυπεῖσθαι πλέον ἕπεται (663 B).
Distinct statement in the Protagoras. What are good and evil, and upon what principles the scientific adviser is to proceed in discriminating them. No such distinct statement in the Gorgias.
In the Gorgias, too, Sokrates declares that some pleasures are good, others bad — some pains bad, others good. But here he stops. He does not fulfil the reasonable demand urged by Sokrates in the Protagoras — “If you make such a distinction, explain the ground on which you make it, and the end to which you look“. The distinction in the Gorgias stands without any assigned ground or end to rest upon. And this want is the more sensibly felt, when we read in the same dialogue, that — “It is not every man who can distinguish the good pleasures from the bad: a scientific man, proceeding on principle, is needed for the purpose”.[77] But upon what criterion is the scientific man to proceed? Of what properties is he to take account, in pronouncing one pleasure to be bad, another good — or one pain to be bad and another good — the estimate of consequences, measured in future pleasures and pains, being by the supposition excluded? No information is given. The problem set to the scientific man is one of which all the quantities are unknown. Now Sokrates in the Protagoras[78] also lays it down, that a scientific or rational calculation must be had, and a mind competent to such calculation must be postulated, to decide which pleasures are bad or fit to be rejected — which pains are good, or proper to be endured. But then he clearly specifies the elements which alone are to be taken into the calculation — viz., the future pleasures and pains accompanying or dependent upon each with the estimate of their comparative magnitude and durability. The theory of this calculation is clear and intelligible: though in many particular cases, the data necessary for making it, and the means of comparing them, may be very imperfectly accessible.
[77] Plato, Gorgias, p. 500 A. Ἆρ’ οὖν παντὸς ἀνδρός ἐστιν ἐκλέξασθαι ποῖα ἄγαθὰ τῶν ἡδέων ἐστὶ καὶ ὁποῖα κακά; ἢ τεχνικοῦ δεῖ εἰς ἕκαστον; Τεχνικοῦ.