Clarifying the Natural Law Thesis

[Extract]
The core claims of natural law jurisprudence have been expressed in many different ways. One useful way of understanding the tradition, however, is through reference to what Mark Murphy has called the natural law thesis: law is necessarily a rational standard for conduct.1 The natural law thesis holds that a norm or system of norms that does not serve as a rational standard for conduct is necessarily invalid or defective as law. Proponents of natural law jurisprudence characteristically affirm the natural law thesis, while legal positivists characteristically deny it.