 According to Lange (cf. 2005, chapter 4; 2009a, chapter 2), there exist several different stable sets: for example, the set of logical truths, the set of all physical laws, and the set of all truths (which is trivially stable). The requirement of \(G\) to be non-maximal, i.e., to be strictly smaller than the set of all truths, is necessary to avoid the identification of the set of laws with the set of all truths.