Yet another tweak of the knowledge argument against physicalism

Here is a variant on the knowledge argument:

1. All empirical facts a priori follow from the fundamental facts.

2. The existence of consciousness does not a priori follow from the fundamental physical facts.

3. The existence of consciousness is an empirical fact.

4. Thus, there are fundamental facts that are not fundamental physical facts.

In support of 2, note that we wouldn’t be able to tell which things are conscious by knowing their physical constitution without some a posteriori data like “When I say ‘ouch’, I am conscious.”