 Further reading: For a variation of the Sixth Meditation argument for the existence of the external material world, see Descartes’ Prin. 2.1. See also Friedman (1997), Garber (1992), and Newman (1994). On the respects in which the Sixth Meditation inference draws on Fourth Meditation work, see Newman (1999). For an interpretation of the Sixth Meditation argument that’s consistent with a direct realist interpretation, see Carriero (2009, 146ff).