Another point against dualism: There is strong scientific evidence that most decisions are not actually made on a conscious level, and that "introspection" about such decisions is handled by the same portion of the brain which generates conversational narratives. That is, your brain is deciding stuff without the conscious mind being aware of it and then retroactively makes up a story when the conscious mind wonders why it did what it just did.
E: HugoLuman, that's actually backed up by the same research I mention. The real "you" (the one that is making choices) is actually best modeled as several disjoint processes in communication. At a minimum, there's one process for interpreting sound, one for vision, one for olfactory senses, one for proprioception, a 'narrator' that comes up with credulous, "most simple answer first" explanations for what those sense processes are reporting, a 'skeptic' that looks for flaws in the current narrative and forces a reboot if enough flaws are found, a 'reflective' process that pretends to be someone else so that you can empathize with other people, an automatic reflex system and at least a couple biological process monitors. The ideal you is just a character in the narrator's story, who for the sake of simplicity, is treated as a single indivisible whole that makes choices for abstract, logical reasons.