Natural law or the law of nature (Latin: lex naturalis) is a theory that posits the existence of a law whose content is set by nature an that therefore has validity everywhere. The phrase natural law is sometimes opposed to the positive law of a given political community, society, or nation-state, and thus can function as a standard by which to criticize that law. In natural law jurisprudence, on the other hand, the content of positive law cannot be known without some reference to the natural law (or something like it). Used in this way, natural law can be evoked to criticize decisions about the statutes, but less so to criticize the law itself. Some use natural law synonymously with natural justice or natural right (Latin ius naturale), although most contemporary political and legal theorists separate the two.