The 'argument by paraphrase' from Counterfactuals is insufficient to establish Lewis's form of modal realism

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 pos