Quote 1
Winston refuses to see five fingers when O'Brien holds up four fingers, even if the Party says there are five fingers, not four. This is an example of Winston refusing to yield to the Party's doctrines (doublethink).
O'Brien: 'How many fingers am I holding up, Winston?'
Winston: 'Four.'
O'Brien: 'And if the Party says that it is not four but five--then how many?'
Winston: 'Four.'
Part 3, Chapter 2