what motivates to express these ideas now, and in front of O'Brien, an Inner Part member? What does this reveal about Winston's character evolving?

"We believe that there is some kind of conspiracy, some kind of secret organization working against the Party, and that you are involved in it. We want to join it and work for it. We are enemies of the Party. We disbelieve in the principles of Ingsoc. We are thought-criminals. We are also adulterers. I tell you this because we want to put ourselves at your mercy. If you want us to incriminate ourselves in any other way, we are ready."