For one, they are supposed to stoke the perception that Mr. Bush, whose campaign has raised record sums, is the candidate of the well off.
Indeed, Mrs. Clinton's campaign moved quickly today to stoke the perception that Mr. Lazio was in a bit of a predicament.
But an interesting question unfolding is whether there is a tipping point at which a candidate becomes so associated with falsehoods that it becomes part of his public persona — which hampered Vice President Al Gore during his run for president in 2000, when his misstatements on the campaign trail were used to stoke the perception that he could not be trusted in general.
Mr. Kerry's aides stoked the perception by disputing the debate commission's decision to place blinking lights on the candidates' lecterns to signify when their time was up.
These outbursts stoked the perception that the Brotherhood, sometimes portrayed in the west as the moderate face of political Islam, is in fact an incubator for more extremist brands of Islamism such as Isis or al-Qaida – a perception that led some to justify Rabaa's violent dispersal, claiming it was the only way to defend against a similar wave of extremism in Egypt.
Despite warnings before the vote that Brexit would shatter economic confidence, some positive economic data and SoftBank's $32 billion takeover of Britain's technology company ARM have stoked the perception that Britain could prosper outside the EU.
Brian Philips, the general manager of CMT, said the show also sought to stoke "a viewer perception that all great artists, all great musicians, know everybody else's songs".
The public's anger at higher prices has been stoked by a perception that the government is mishandling the economic downturn, and mismanaging public finances.
That racial resentments simmer below the surface and stoke at least some of these perceptions is hard to quantify and impossible to deny.
This sense of heightened insecurity was further aggravated by ideological Israeli and Palestinian leaders that made little or no effort to correct these perceptions, deciding instead to stoke nationalist fervor and angst against the "Other".
