In Book 3, Ch. 3 what does winston say will eventually destroy the party? how does O'Brien respond to Winston's remarks?

From the text:

‘You could not create such a world as you have just described. It is a dream. It is impossible.’

‘Why?’

‘It is impossible to found a civilization on fear and hatred and cruelty. It would never endure.’

'Why not?'

‘It would have no vitality. It would disintegrate. It would commit suicide.’

‘Nonsense. You are under the impression that hatred is more exhausting than love. Why should it be? And if it were, what difference would that make? Suppose that we choose to wear ourselves out faster. Suppose that we quicken the tempo of human life till men are senile at thirty. Still what difference would it make? Can you not understand that the death of the individual is not death? The party is immortal.’