Which quotes best describe Squealer's traits and importance in George Orwell's Animal Farm?

Squealer is described as a clever speaker. At the beginning of the book, he is painted in the following way: 




"He was a brilliant talker, and when he was arguing some difficult point he had a way of skipping from side to side and whisking his tail which was somehow very persuasive. The others said of Squealer that he could turn black into white" (page 6).

Squealer is so good at convincing others of his point of view that he can literally make black into white and make things that aren't true appear to be true. His importance is that he keeps the animals in line and maintains the pigs' top position in the hierarchy through his speeches. 
Squealer later uses his considerable powers of persuasion to tell the other animals that the pigs are justified in drinking all the farm's milk and eating the windfall apples. He says:




"Milk and apples (this has been proved by Science, comrades) contain substances absolutely necessary to the well-being of a pig. We pigs are brainworkers. The whole management and organisation of this farm depend on us" (page 14).

Squealer convinces the other animals to allow the pigs to eat all the best food because it's in the other animals' interest to do so. He makes the pigs' selfishness seem like altruism, and he backs up his arguments with pseudoscience. Whenever the other animals are even thinking about disagreeing with him, he cleverly asks them, "Surely, comrades, you do not want Jones back?" (page 22). He equates disagreeing with him to bringing back the old regime with Jones, and he frightens the others into agreeing with him.