After arguing that infallibilism faces serious problems, this chapter turns to consider objections levelled at fallibilism. Chapters 5 and 6 consider the objection that fallibilism undermines closure for knowledge. In reply, it’s been argued that closure fails for reasons quite independently of the fallibilism–infallibilism debate, specifically because of defeat. If that’s right, then closure provides no reason to prefer infallibilism over fallibilism. However, the very idea of defeat has come under recent attack. This and the next chapter provide an extended defence of a variety of kinds of defeat. This chapter provides a positive argument for rebutting and undermining defeat. It also examines and rejects some recent objections to rebutting defeat, including Lasonen-Aarnio’s objection that rebutting defeat fails to answer the dogmatism puzzle.