 Philosophers have long made introspective claims about the human mind—or, to speak more cautiously, they’ve made claims seemingly at least in part introspectively grounded. Aristotle (3rd c. BCE/1961) asserts that thought does not occur without imagery. Mengzi (3rd c. BCE/2008) argues that our hearts are pleased by moral goodness and revolted by evil, even if the pleasure and revulsion are not evident in our outward behavior. Berkeley finds in himself no “abstract ideas” like that of a triangle that is, in Locke’s terms “neither oblique, nor rectangle, neither equilateral, equicrural, nor scalenon, but all and none of these at once” (Berkeley 1710/1965, 12; Locke 1689/1975, 596). James Mill (1829 [1878]) attempts a catalog of the varieties of sense experience.