This is Winston's story, and we only get information through his eyes. Why does this work? Part of what makes 1984 awesome is that we feel the same emotions as its protagonist. If Winston feels confused about history, we are likewise confused as we try to understand the system of Oceania. Winston is confronted with the irony of his love and hate for certain characters, just as we marvel at the irony of the places and slogans of the party. By having to read the brutal and explicit language of the torture scene, we are similarly tortured. We become Winston - until his departure from free will at the end. Then we feel particularly awful since we have gotten used to sympathizing with him, to experiencing things with him. And this experience that you, the reader, go through is made possible by the Third Person Limited Omniscient Narrative Technique.