In Chapter 5, Piggy asks Percival Wemys Madison to speak about fears. Percival is terrified of speaking to the group of boys. Piggy asks him to say his name, but he cannot. Then Ralph sharply orders Percival to speak. Percival begins to speak, announcing his name and address first as he was taught. He cannot, however, quite remember his telephone number. He begins to cry and other littluns join in. This illustrates that Percival is losing the memory of civilization, a place the littleuns believe is safe and not inhabited by the beast. When Ralph yells at Percival to speak, Golding reveals that the the boys now respond more to fear and intimidation than logic and reason. This is an observation that Jack will exploit more and more as the novel continues.
Percival Wemys Madison's rote recital earlier in the novel (Chapter 4) of his name, address and telephone number show simply the way that civilised behaviour has been repeatedly instilled in him by his parents.
Percival at the meeting out of nerves initially cannot announce his name, but then habit takes over, and Percival repeats his name and address - but not his telephone number. Percival's civilised incantation is a good benchmark for the disintegration of the boys' civilisation: and here in Chapter 5, we can actually see civilisation starting to crumble into savagery. Percival's incantation is beginning to fade.
By Chapter 12, of course, when savagery has taken grip, Percival remembers nothing of his incantation: it has "faded clean away".
I agree with both answers as provided above.
Has anyone stopped to wonder why Golding provides "St. Anthony's" as the name of the school Percival attended?
I think this may have some symbolic importance to the story as well, though I am definately not an expert.
If you were to do a search for Saint Anthony, you may find that he is a patron saint for of many things, including epilepsy.
In works of art, St Anthony is usually portrayed with 4 symbols: Tau, a bell, a pig, and fire or flames.