“So it seemed to be beyond question that the measurable dimensions of an object, say its thermometer temperature or its speed in yards per second, characterized it in the same general sort of way as its colour or taste were naively supposed to do. It seemed natural to list them both as Qualities. It then seemed necessary to draw a line between the qualities which have to be mentioned and operated with in physical theory and the qualities which cannot. They were in fact so distinguished—first, I believe, by Boyle—as the ‘Primary’ and ‘Secondary Qualities’ respectively. But then the scientifically blue-blooded Primary Qualities could not tolerate sharing a bench with the rude Secondary Qualities, and these had, in consequence, to be deprived of their title to be qualities of things at all. Clearly the mistake was to put them on the same bench at the start, but Aristotle’s economy in benches was not yet recognized to be a piece of personal stinginess.”
If only all philosophical writing were this lucid and trenchant. Aristotle’s economy in benches was not yet recognized to be a piece of personal stinginess. What a joy it is to read Ryle!