 The little ‘argument by paraphrase’ from Counterfactuals is a long way from an argument for Lewis’s form of modal realism. For one thing, the argument relies on taking a folksy paraphrase as metaphysically revealing; perhaps we would be better off treating this as just a careless manner of speaking. For another, the folksy paraphrase Lewis uses isn’t obviously innocuous; like many other abstraction principles it could be hiding a contradiction. And the argument does little to show that other possible worlds are concreta; talking of them as ways things could be makes them sound like properties, which are arguably abstracta if they exist at all. The first three chapters of Plurality address these three issues. The fourth chapter is an extended discussion of the place of individuals in modal realism. We’ll look at these chapters in order.