  He similarly seems to identify the real essence of bodies with primary qualities when he suggests, just prior to the “microscopical eyes” passage, that instead of seeing colors (or instead of seeing them as we currently do), we could discover bodies’ internal constitutions, if only we knew the ”texture and motion of the minute Parts of corporeal things“ (E II.xxiii.12, pp. 302–303). And a commitment to the corpuscular hypothesis is again suggested when he despairs of understanding the production of secondary qualities: even if “we could discover the size, figure, or motion of those invisible parts, which immediately produce them [secondary qualities],” we still cannot discover any “undoubted Rules” concerning their production or connection, nor “conceive how any size, figure, or motion of any Particles, can possibly produce in us the Idea of any Colour, Taste, or Sound” (E IV.iii.13, p. 545). Here he appears to despair of understanding how secondary qualities are produced by primary ones; he appears to take the corpuscular hypothesis’ reductionist claim to be true, but he despairs of our understanding how the reduction works.