Argument from Causation: Externalists insist that wide content can be causally relevant. The details vary among externalists, and discussion often becomes intertwined with complex issues surrounding causation, counterfactuals, and the metaphysics of mind. See the entry mental causation for an introductory overview, and see Burge (2007), Rescorla (2014a), and Yablo (1997, 2003) for representative externalist discussion.