 According to a simple theory, G experiences represents greenness, and R experiences represent redness. An objection to this theory arises from a putative case of inverted qualia without illusion. The case goes like this. One perceiver, call her Nonvert, typically has R-experiences when she veridically perceives and is in causal contact with red things, and she typically has G-experiences when she veridically perceives and is in causal contact with green things. Another perceiver, call him Invert, typically has R-experiences when he veridically perceives and is in causal contact with green things, and has G-experiences when he veridically perceives and is in causal contact with red things. So, in the thought experiment, when Invert, with his G-experiences, sees a red tomato, his experience represents redness; when Nonvert sees the same tomato with his R-experiences, his experiences also represents redness.