Winston’s worst fear in the Ministry of Love is rats. In Room 101, O’Brien has a cage of starving rats placed over Winston’s face, threatening to let them attack him. The Party uses this carefully chosen terror to break the last of his resistance.
Earlier in Nineteen Eighty-Four, Winston’s fear of rats is already suggested when he sees them in the rented room above Mr. Charrington’s shop. The Ministry’s torture is not merely physical: it turns a private phobia into a weapon against Winston’s loyalty to Julia and his remaining sense of self.
Room 101 is designed around each prisoner’s deepest fear, so the experience differs from person to person. For Winston, the rats are the decisive instrument. He begs the authorities to inflict the ordeal on Julia instead, betraying her in the process. The scene demonstrates the Party’s goal: not simply obedience, but the destruction of independent love, memory, and belief.