Mereology (“mee-ree-ology”) unproblematically incorporates an analogue of these objects’ rule of unrestricted comprehension, which was originally called Basic Law V (“five”). Type theory was developed to resolve a paradox about these objects, which is often compared to a barber who can’t shave himself. (10[2])Gottlob Frege (10[1])(“FRAY-guh”) defined numbers as these objects, which is also done in Zermelo-Frankel theory. The naïve theory of these objects is subject (10[2])to Russell’s paradox, which concerns one of these objects containing all of these objects that do not contain themselves. De Morgan’s laws (10[1])axiomatize (10[1])the union and (10[1])intersection operations on these objects. For 10 points, name these unordered collections of objects. ■END■