The formal establishment of the modern nation-state system through the Treaties of Westphalia (1648) gave birth to modern international law. At its onset in the 17th century, international lawyers and philosophers debated the essence of international law and its principal source. Naturalists argued that international laws should flow from natural law, which draws on sources in nature or religion and, therefore, should be based in morality. Positivists countered by arguing that international laws, as contracts among states, are so-called positive law, produced by negotiations and have a political rather than moral basis.  The implications of this early jurisprudence debate were significant, in effect pitting the rights and needs of individuals (protected by nature-based laws) against the power of states (promoted by negotiated laws). Over the course of the 18th century, the positivist philosophy of international law prevailed. As a result, the global legal order is one in which states are independent and negotiate the international rules that regulate their own behaviour. While international law may reflect morality, it is not a requirement in a positivist legal order. It should be noted, however, that since the Second World War moral principles have increasingly been the subject of binding international agreements. This is most prevalent in human rights treaties, in laws that protect refugees, and in the more recent R2P concept.