 Heal (1994) pointed out a problem with committing ST to a particular account of the cognitive mechanisms that underlie it. Suppose that the human mind contains two distinct decision-making mechanisms: Mec1, which takes beliefs and desires as input, and generates decisions as output; and Mec2, which works by following exactly the same logical principles as Mec1, but takes imagined beliefs and imagined desires as input and generates imagined decisions as output. Consider again Frank’s decision to enter Central Café and my imagined decision to do so. According to the two mechanisms hypothesis, Frank desired to drink a beer and believed that he could buy one at Central Café, fed these mental states into Mec1, which generated the decision to enter the café. As for me, I fed the imagined desire to drink a beer and the imagined belief that I could buy one at Central Café into a distinct (type of) mechanism, i.e., Mec2, which generated the imagined decision to enter Central Café. Here is the question: does my imagined decision to enter Central Café count as a mental simulation of Frank’s decision to do so? If your answer is “Yes, it does”, then  RES+REU  is in trouble, since my imagined decision was not generated by reusing the same (type of) cognitive mechanism that Frank used to generate his decision; his decision was generated by Mec1, my imagined decision by Mec2. Thus, Heal concludes, a definition “mental simulation of” should not contain any commitment about cognitive mechanisms—it should not make any implementation claim—but should be given at a more abstract level of description.