Plutarch Quaestiones Convivales 9.13.3

[3] Glaucias subjoined: In all laws, decrees, contracts, and promises, those latest made are always accounted more valid than the former. Now the later contract was Agamemnon’s, the condition of which was killing, and not only overcoming. Besides the former was mere words, the latter confirmed by oath; and, by the consent of all, those were cursed that broke them; so that this latter was properly the contract, and the other a bare challenge. And this Priam at his going away, after he had sworn to the conditions, confirms by these words:

for he understood that to be the condition of the contract. And therefore a little after Hector says, for the combat had not its designed and indisputable determination, since neither of them fell. Therefore this question doth not seem to me to contain any contrariety of law, since the former contract is comprised and overruled by the latter; for he that kills certainly overcomes, but he that overcomes doth not always kill. But, in short, Agamemnon did not annul, but only explain the challenge proposed by Hector. He did not change any thing, but only added the most principal part, placing victory in killing; for that is a complete conquest, but all others may be evaded or disputed, as this of Menelaus, who neither wounded nor pursued his adversary. Now as, where there are laws really contrary, the judges take that side which is plain and indisputable, and mind not that which is obscure; so in this case, let us admit that contract to be most valid which contained killing, as a known and undeniable evidence of victory. But (which is the greatest argument) he that seems to have had the victory, not being quiet, but running up and down the army, and searching all about, sufficiently testifies that he himself did not imagine that the conquest was perfect and complete when Paris had escaped. For he did not forget his own words: Therefore it was necessary for him to seek after Paris, that he might kill him and complete the combat; but since he neither killed nor took him, he had no right to the prize. For he did not conquer him, if we may guess by what he said when he expostulated with Jove and bewailed his unsuccessful attempt: For in these words he confessed that it was to no purpose to pierce the shield or take the head-piece of his adversary, unless he likewise wounded or killed him.