What was winston’s point of view on perception?

I think you are referring to Part 3 of the book during Winston's interrogation. Winston claims that there are certain laws to perception. Truth is truth no matter how hard one tries to bend it: 2+2=4. O'Brien argues that this is nonsense: truth and perception is whatever the party tells you it is.

O'Brien: I could float off this floor like a soap bubble if I wish to. I do not wish to, because the Party does not wish it. You must get rid of those nineteenth-century ideas about the laws of Nature. We make the laws of Nature.