 S-naturalism has played a significant role in at least three legal-philosophical traditions: (1) the Scandinavian Legal Realists (like Alf Ross and Karl Olivecrona), whose austere ontological naturalism, conjoined with moral anti-realism, shaped their distinctive take on legal concepts; (2) Legal Positivists, for whom S-naturalism can be, and sometimes has been, a significant motivation, and (3) contemporary defenders of a kind of natural law theory (like David Brink, Michael Moore, and Nicos Stavropoulos), who invoke the Causal Theory of Reference associated with Kripke and Putnam to offer an interpretation of some legal predicates in substantively naturalistic terms.