 Responses (i) and (ii) will be discussed in  Section 7.  Regarding response (iii), one Fregean theory about this thought experiment is that it is a case in which the experiences of Invert and Nonvert have different modes of presentation of the same color property (say, redness). On this view, redness would be presented in Invert’s experience under a G-mode, and it would be presented in Nonvert’s experience under a R-mode, so that the phenomenal difference between Invert and Nonvert’s experience would also be a difference in Fregean content.