 Qualitative Supervenience  If \(f\) is a bijection from the objects existing at \(w\) to the objects existing at \(w'\) such that for every perfectly natural \(n\)-ary property \(R\) and objects \(x_1,\ldots ,x_n\), \(x_1,\ldots ,x_n\) instantiate \(R\) at \(w_1\) iff \(f(x_1),\ldots ,f(x_n)\) instantiate \(R\) at \(w_2\), then for every qualitative \(m\)-ary property \(S\) and objects \(y_1,\ldots ,y_m\), \(y_1,\ldots ,y_m\) instantiate \(S\) at \(w_1\) iff \(f(y_1),\ldots ,f(y_m)\) instantiate \(S\) at  \(w_2\).[28] 