Sources Thesis: All law is source-based, i.e. its existence and content can be determined by reference to social facts alone.
Incorporation Thesis: All law is either source-based or entailed by source-based law (e.g. if the law says “There shall be no unfair discrimination” then the content of that prescription can be determined solely by reference to social facts or whatever is entailed by those social facts).
Coherence Thesis: The law consists of source-based law together with the morally soundest justification of source-based law (Ronald Dworkin’s view of law).