Praeteritio is the device of raising something by announcing that you will not raise it. The speaker names the subject in the act of setting it aside, and the audience hears it perfectly well — while the speaker retains the posture of having been too fair-minded to bring it up.
It is the only device in this library whose entire effect depends on the audience not quite noticing what has happened.
Cicero was its great practitioner. Prosecuting Verres, he repeatedly declines to mention charges he is in the middle of describing: he will say nothing of the man's thefts, nothing of his cruelty, nothing of the provinces he stripped — having by then said all three. The jury has heard every accusation, and Cicero has technically made none of them.
Also called apophasis or paralipsis. The English giveaway is almost always a clause beginning “I won't even mention…” or “Never mind that…”
Becomes Poisoning the Well when the thing not-mentioned is an attack.
Praeteritio exploits an asymmetry between what an audience hears and what a speaker can later be held to. Information delivered inside a refusal to deliver it is still information, but it has not been asserted, and so it cannot easily be challenged, corrected, or made the subject of an apology. The speaker keeps the benefit and declines the liability.
In its honest form the device is a matter of economy. A writer with ten arguments and room for three may legitimately gesture at the others to show that the case is broader than the space allows. Nothing is smuggled, because nothing turns on the items passed over.
The dishonest form is more common, and it is recognisable by what happens when you delete the clause. If the passage loses nothing — if the thing not-mentioned was doing no argumentative work and was simply damaging — the device was not economy but insinuation. At that point it has stopped being a figure of speech and become an attack conducted at one remove, which is why it sits so close to poisoning the well.
It survives because it is socially difficult to object to. Challenging a praeteritio means repeating the accusation on the speaker's behalf, which does their work for them a second time.
