 In Hutcheson’s psychology there is a key difference between the external and internal senses. According to Hutcheson, the external senses have the power to perceive simple ideas—notes, colors, sounds, tastes, etc. (Inquiry, 23). But the internal senses are those, according to Hutcheson, that arise “only upon some previous Idea, or Assemblage, or Comparison of Ideas” (Essay, 15–16). The internal senses, then, will proliferate under Hutcheson’s general account—any capacity to generate pleasure or pain involuntarily given the comparison of ideas will, on Hutcheson’s view, be a sense. And hence it should not at all be surprising that Hutcheson gives the diverse accounting of senses that he does.