 The argument, I suggest, is best construed as an inference to the best explanation. The best explanation of a) that it is impossible to have a rational argument about what is good or bad in itself and b) that in such disputes there can be nothing beyond “an appeal to individual tastes” is the hypothesis c) that there is nothing objective to disagree about since there is no such thing as goodness—rather our opinions on these topics are somehow dependent on, or expressive of, our disparate desires and perhaps our diverse upbringings.