Deception and Incorporeality

The possibility that Descartes is an incorporeal being enters the Meditations in two ways--as an inference from the example of dreaming, and as a consequence of the hypothesis that God is evil.  But, the inference from dreaming is invalid.  For, the deception in dreaming consists in a discrepancy between two corporeal scenarios, e. g. between one running, and one sleeping in a bed with legs twitching.  Thus, the extrapolation to a discrepancy between a corporeal scenario and an incorporeal one is ungrounded, e. g. a brain in a vat is as much a corporeal entity as the full body that it is stimulated to imagine.  Furthermore, once the hypothesis that God is evil is refuted, in the Third Meditation, so, too, is part of the consequence of that hypothesis, namely, the thesis that Descartes is actually an incorporeal entity.  So, Mind-Body Dualism does not follow in the Meditations from a rigorous exercise of his Method, but it could reflect a prejudice central to his Theological affiliation, i. e. the separation of Soul and Body.