Why does O'Brien call Winston the "last man" in 1984?

During
's torture in the Ministry of Love,is attempting to make Winston give up hope that humanity will
prevail and the citizens will successfully rebel against the Party. Winston believes in the
indomitable spirit of Man and tells O'Brien that he considers himself a man. O'Brien replies by
saying,

If you are a man, Winston, you are the last man.
Your kind is extinct; we are the inheritors (, 340).

By
calling Winston the last man, O'Brien is emphasizing the Party's superiority and complete
control over humanity. The Party has cultivated an environment where virtually every citizen
reveres, worships, and fears Big Brother. The Party is also in the process of completely
eradicating independent thought, and Winston is one of the last remaining political dissidents,
who believes in independence and autonomy from the government. O'Brien is also highlighting the
futility of Winston's rebellion against the Party by calling him the last man. He is essentially
encouraging Winston to give up his pursuit of independence and completely embrace Big Brother
and everything the Party represents.