 We can suggest a different solution. Locke’s remarks about what he calls “idea” and “quality” in E 2.8.8 are not definitions by his lights; see E 3.3.15–7 on real and nominal essence. They are more like sufficient conditions for being designated by the terms “idea” or “quality.” Being a power is sufficient for being designated by “quality,” as shown by color, etc., but it is not necessary, as shown by the PQs of insensible particles which are not powers to cause ideas, but constituents of such powers. McCann (2011: 59–67) argues that the PQs found in the microstructures of bodies are the causes of both ideas of SQs and ideas of the PQs of sensible bodies. He urges a divsion of types of PQs based on a division of labor—insensible PQ are primary PQs whereas PQs of gross bodies are secondary PQs. For other solutions to the present issue, see Rickless (2014: 85), Stuart (2013: 34–9), R. Wilson (2015: 207–8).