It would be arbitrary to suppose that Invert's color vision, but not Nonvert's, is the source of pervasive illusions if both are equally useful for discrimination and identification
Pervasive illusions(as used in epistemology (the study of knowledge))
False beliefs or misperceptions that are widespread and constant, affecting many situations or judgments rather than just one isolated case.
Qualia (or color qualia)(as used in philosophy of mind)
The subjective, personal experience of what something feels or looks like to you—like what redness actually feels like in your mind. Two people might call the same thing 'red,' but their inner experience of that color could be different.
The source of illusions(as used in epistemology)
What causes false perceptions—in this case, whether someone's color vision is creating misleading experiences about what colors actually are.
arbitrary(Debate over Locke's watch passage and natural kind classification)
Does not mean 'random' or that all qualities are equally adequate as differentia; refers instead to the availability of multiple similarly good and natural grounds for classification.
The three features of the anti-representationalist scenario can motivate the conclusion that Invert is not systematically misperceiving the colors of things as follows. First, because Invert’s color vision is as useful as Nonvert’s for discriminating and identifying objects, surely it would be arbitrary to suppose that Invert’s color vision, but not Nonvert’s, is the source of pervasive illusions. Second, because Nonvert has been inverted since birth, a complicated system of causal connections b