Comment by TKoL on Are David Chalmers' definitions of strong and weak emergence scientifically testable when applied to consciousness as emerging from physics?

There is indeed a clear essential difference between weak and strong emergence. Weak emergence doesn't require any deviation from low-level things following their own low-level rules. Strong emergence, however, does - that's what "downward causation" is about. It means the higher level thing makes a causal difference on the lower-level things.