It is hard to avoid the conclusion that Orwell intended to use Squealer as an example of how totalitarian governments can control their people through the manipulation of language. Squealer, who we are told, "could turn black into white," emerges as a sort of propaganda minister for the pigs in general and Napoleon in particular. He uses language and rhetoric throughout the book to steel the animals for the privations they must face and especially to justify departures from the principles of the rebellion. He is very persuasive, as the following excerpt, in which he defends the decision by the pigs to trade with the surrounding farms (contrary to a resolution they had passed at the beginning of the rebellion) suggests:
“Are you certain that this is not something that you have dreamed, comrades? Have you any record of such a resolution? Is it written down anywhere?” And since it was certainly true that nothing of the kind existed in writing, the animals were satisfied that they had been mistaken.
It is Squealer who invents the slogan "Napoleon is always right," who refashions Snowball into a sort of bête noire of the farm, and who teaches the sheep to bleat first "four legs good, two legs bad," and then, once the pigs begin walking on two legs, "four legs good, two legs better!" He also is able to quickly explain away one of the worst transgressions the pigs commit when Boxer is sent away in the knacker's wagon, which he claims actually belongs tto the veternarian. So Squealer is used to demonstrate the power of language to reinvent or construct reality in the service of power.