In more than one way, Huxley's Brave New World stands out as a complete opposite to George Orwell's 1984. For example, in Orwell's novel emotions are completely squashed. Stoicism is the name of the game. There is no anger and hatred, but there also isn't any joy and happiness either. Huxley's book may show a control of society's emotions, but it's a control over the negative. Everybody is kept artificially happy through drugs. They are encouraged to be sexually promiscuous too, unlike in 1984.
There are other differences between the two novels for sure, but one thing both authors agreed on was that control and manipulation of the past is very important for keeping a present society under control. In 1984 it's described like this:
"And if all others accepted the lie which the Party imposed – if all records told the same tale – then the lie passed into history and became truth. "Who controls the past," ran the Party slogan, "controls the future: who controls the present controls the past." And yet the past, though of its nature alterable, never had been altered. Whatever was true now was true from everlasting to everlasting. It was quite simple. All that was needed was an unending series of victories over your own memory. "Reality control," they called it: in Newspeak, "doublethink."
Brave New World states the history philosophy with much more brevity.
"You all remember," said the Controller, in his strong deep voice, "you all remember, I suppose, that beautiful and inspired saying of Our Ford's: History is bunk. History," he repeated slowly, "is bunk. . . "That's why you're taught no history," the Controller was saying."
In one novel, history is changed to match current government policy. In the other novel no history is taught. Two different methods that both serve the same end function. People cannot see what history was really like. They can not compare their current situation to past events. If they can't compare, they have no way of knowing if they are better or worse off than before. In Brave New World that serves the government just fine. If citizens can't look back at history's and science's mistakes, they are much more willing to accept current policy and focus on future progress. And in Brave New World, future progress is all about maximizing happiness to keep the population docile and mold-able. That's why the World State keeps people ignorant of history; it's to keep them always looking forward . . . at what they are told to look at.