Clinton’s achievements were a problem. In strategy meetings, he often complained that he had created seven million jobs and cut the deficit but no one seemed to notice. In speeches, he referred to the achievements awkwardly. Our polls showed audiences already knew about them or didn’t believe they were true.

The solution, apparently, was a re-jiggering of language. Morris relates that communications strategist Bob Squier had the following bright idea:

The key…was to cite the achievement while talking about something he was going to do. For example: “The hundred thousand extra police we put on the street can’t solve the crime problem by themselves; we need to keep anti-drug funding in the budget and stop Republicans from cutting it.” Or: “The seven million jobs we’ve created won’t be much use if we can’t find education people to fill them. That’s why I want a tax deduction for college tuition to help kids go on to college to take those jobs.”

Linguists of course will recognize that this language is infested with presuppositions—those fascinating linguistic organisms, which because of theirpresumption

of truth, head deniability off at the pass. There are no fewer than six distinct, politically-relevant presuppositions in the above brief excerpt.

Once you know about the linguistic properties of presuppositions, it seems intuitively natural that they should act as performance-enhancing aids for claims, particularly when it comes to believability. After all, their entire reason for living is to allow the speaker to signal that certain information is already taken for granted as shared knowledge—and if it’s not, then the hearer should accommodate it post-haste into his set of background assumptions.

In fact, psychological studies as far back as the seventies have shown that people can be so eager to accommodate presupposed information that they might even tweak their own memories accordingly. In a study led by memory scientist Elizabeth Loftus, people who’d witnessed simulated car crashes were more likely to mistakenly remember a stop sign when asked ”Do you remember seeing the stop sign?” 

as opposed to “Do you remember seeing a stop sign?”
from an unusually useful Language Log post