Greek audiences adored debate, as they adored every kind of contest, and playwrights obliged by writing formal debates into many plays. These are usually about equal in length, as fair play in a debate demands, and they often employ popular tools of rhetoric that sound too studied and contrived for a modern audience to accept as dialogue in a play. Often, also, to the distress of modern readers, they do not directly advance the action of the play.
By contrast, Henry V in Shakespeare’s play delivers a number of highly rhetorical set-piece speeches, but we do not hear them that way, because the rhetorical devices are cleverly hidden, and because he is not opposed (as a Greek tragic king would be) by equal speeches from the opposite side. Henry’s stage audiences miss the rhetorical cleverness also; they are simply moved to surrender, or to fight, or (as in the case of the conquered princess) to consent to marriage.
A translator of Greek plays may choose between making the lines of a speech actable on the modern stage and bringing across the exercise it contains in formal rhetorical technique. Or the translator can try to make the rhetoric seem plausible in context. Sophocles makes this easy in Antigone, where Creon and his son debate in equal speeches and using arguments that balance one another. There, the debate represents an initial stage in the quarrel between the two men, in which they both try to be respectful and decorous, their passions held back by the formality of the debate. This changes in the line-on-line debate that follows, a more flexible form that allows respect to modulate quickly into rage.
Such exchanges of one-liners (stichomythia) are ubiquitous in Greek plays. These too are a kind of contest, a sort of verbal tennis, in which each speaker seizes on a word the other had just used, and turns it against him. A translator whose eye is on the character of the speakers or on the precise content of the lines would have to leave this behind, if the same word calls for different renderings in different lines. The challenge to the translator is to make the exchanges seem plausible while conveying the meaning of the original and bringing out the elements of verbal contest in the scene.