 Hume ([1739] 1962: 252) seems to have been an example of the strongest form of scepticism. He famously doubted, or tried to doubt, that we have unified consciousness even of the self, let alone of one’s conscious states. Among recent writers, perhaps the most sceptical about consciousness being unified is Rosenthal. Rosenthal holds that all we have is a “sense of the unity of consciousness” (1986: 344, emphasis added). Why merely a sense? On his view, 