Often I sit pondering the possiblities of this equation, and I am always left with the same conclusion.
I know that the point of this was to prove the irrational belief required to survive in a 1984 destopia. But when you think about it more clearly there is either one of two things that occur in this sentence.
1) That if you had two apples, and I had two apples if we put them together there would be 5 apples.
or the second option which I think is really being said. The party has the power to make the value of 5 equal the value of 4 and remove four form the lexicon perminately if they ever wished to.
Meaning that 2+2 still would =4 but they no longer say 4 but instead say 5.
The power to change the meaning of words is the ultimate power in 1984 the Party knows this .In changing of the meanings of words it provides the illusion that they are infact great creators. They have the power they are able to manipulate people with unreasonable logic, doctor history to fit their arguments, and finally destory ones will to rebel by the ultering of meanings, as it was in throws of pain that Winston eventually releashed his most passionate belief that 2+2=4.