Full Idea
Supervenience is neither symmetric nor asymmetric; it is non-symmetric. Sometimes it holds symmetrically. …And sometimes it holds asymmetrically.
Gist of Idea
Supervenience is non-symmetric - sometimes it's symmetric, and sometimes it's one-way
Source
Karen Bennett (Supervenience [2011], §3.2)
Book Reference
'Stanford Online Encyclopaedia of Philosophy', ed/tr. Stanford University [plato.stanford.edu], p.6
A Reaction
I think of supervenience as 'tracking'. Stalkers track victims; married couples track one another. Beauty tracks statues, but statues don't seem to track beauty. I take so-called mind-brain supervenience to be two-way, not one-way.