Full Idea
The view that causation is primitive can be defended against Humean critics by saying that causation can be directly observed in the will or our bodies, or that it can be inferred as the best explanation.
Gist of Idea
If causation is primitive, it can be experienced in ourselves, or inferred as best explanation
Source
Jonathan Schaffer (The Metaphysics of Causation [2007], 2.1.2)
Book Reference
'Stanford Online Encyclopaedia of Philosophy', ed/tr. Stanford University [plato.stanford.edu], p.22
A Reaction
I like both views, and have just converted myself to the primitivist view of causation! I can't know the essence of a tree, because I am not a tree, but I can know the essence of causation. The Greek fascination with explaining movement is linked.