Natural Law

The expression ‘Natural Law’ is used in three related ways: First, in philosophy of law to refer to the idea that as well as the realm of laws made by legislators (‘positive law’) there is another realm prior to and independent of it by which the justice of positive laws may be judged, this being the natural law or ‘natural justice’. Second, as referring to that part of morality that can be known by natural reason in contrast to that which is only known through revelation, hence: natural vs revealed law. Third, in reference to an approach, and to of set of values and principles advocated by that approach, that are rooted in an account of human nature. Versions of all three are to be found in Plato. An example of this third use is the attempt to establish fair principles of ownership and exchange, of marriage and sexual ethics, etc., based on theories of human nature and of what protects and promotes the human good. Critics of natural law sometimes accuse it of committing the ‘naturalistic fallacy’ by trying to derive ‘ought’ from ‘is’. Defenders hold that the criticism is misconceived in assuming an absolute distinction between facts and values, whereas these are often inextricably linked, thus to say that something is cruel is both to describe and evaluate it.