It seems that democracy -- government for the people, by the people -- is the answer. Throughout the whole book the idea that the proles, i.e. the masses, are the only hope is repeated over and over. It is, as Winston surmises and O’Brien later confirms, the essential truth of Goldstein’s book. This is a pretty obvious reference to democracy; in a true democratic state, the proles would have the most power, as they comprise eighty-five per cent of the population of Oceania.
Power becomes corrupted as soon as it is absolute; as Goldstein’s book says, the leaders of Oceania were, “hungrier for pure power,” which would be the thing to corrupt them. They weren’t “infected… by liberal ideas,” and as such amassed more, and more absolute, power than ever before. This power is definitely presented as evil to the core; the whole book is about rebellion against it, and even Winston’s eventual succumbation to the Party’s ideals and Big Brother is something the reader is supposed to be disgusted