Dirimens Copulatio (di’-ri-mens ko-pu-la’-ti-o): A figure by which one balances one statement with a contrary, qualifying statement (sometimes conveyed by “not only … but also” clauses). A sort of arguing both sides of an issue.
Protagoras (c. 485-410 BC) asserted that “to every logos (speech or argument) another logos is opposed,” a theme continued in the Dissoi Logoi of his time, later codified as the notion of arguments in utrumque partes (on both sides). Aristotle asserted that thinking in opposites is necessary both to arrive at the true state of a matter (opposition as an epistemological heuristic) and to anticipate counterarguments. This latter, practical purpose for investigating opposing arguments has been central to rhetoric ever since sophists like Antiphon (c. 480-410 BC) provided model speeches (his Tetralogies) showing how one might argue for either the prosecution or for the defense on any given issue. As such, [this] names not so much a figure of speech as a general approach to rhetoric, or an overall argumentative strategy. However, it could be manifest within a speech on a local level as well, especially for the purposes of exhibiting fairness (establishing ethos [audience perception of speaker credibility]).
This pragmatic embrace of opposing arguments permeates rhetorical invention, arrangement, and rhetorical pedagogy.
Not only should one tell the truth, but also, one should be prepared to lie when lying is warranted. Let me explain how this pertains to . . .
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Definition and commentary courtesy of “Silva Rhetoricae” (rhetoric.byu.edu).