>>13715650ok i need a better explanation, let's say Y is the set of sets that dont contain themselves, except 1 set, which is y itself, Y = [a,b,c] but as you can see, there is no Y, so let's add Y to it, now it's [a,b,c,Y], so (Y AND the set Y) = [a,b,c,Y], let's call it D, D = [a,b,c,Y], D is the set of sets that don't contain themselves
