 Downing (2007: 354–59) argues that the inseparability criteria are part of a corpuscularian argument for the distinction of qualities which accords with our natural understanding of physics. Locke does not endorse the adequacy or truth of CT but, she contends, he regards it as an imperfect example of an ideal demonstrative physics which would deduce all operations of bodies from their real essences, or internal constitutions (see E 3.3.15; 4.6.11). She suggests Essay 2.8.8 through 14 makes an argument that relies on the implicit ideal (see E 3.3.17). (See Ayers 1981, also Downing 1998)