 But it is controversial whether these forms of supervenience are strong enough to be philosophically useful. As both Shagrir (2002) and Bennett (2004a) have pointed out, only strong global supervenience guarantees that the world-wide distribution of B-properties determines the world-wide distribution of A-properties. Both weak and intermediate global allow what is called ‘intraworld variation’—both allow B-indiscernible individuals in a world to have different A-properties. (Contrast weak individual supervenience, which allows crossworld variation, but does ban “mixed worlds.”) Indeed, weak global supervenience allows the A-preserving and B-preserving isomorphisms to be utterly independent of each other. Suppose some property being griffic merely weakly globally supervenes on the physical. Then although a world physically just like this one has to contain the same number of griffic things as this world, it does not matter which things they are. In this world it might be the Eiffel Tower and the Queen Mother; in the physical duplicate it might be a tea towel and the Grand Canyon.