The scholars who followed Grotius can be grouped into two schools, the naturalists and the 
positivists.In international law, however, the concept 
of natural rights had only marginal significance until the 20th centuryIn contrast, positivist writers, such as Richard 
Zouche (1590-1661) in England and Cornelis van Bynkershoek (1673-1743) in the 
Netherlands, emphasized the actual practice of contemporary states over concepts derived from 
biblical sources, Greek thought, or Roman law.Elements of both positivism and 
natural law appear in the works of the German philosopher Christian Wolff (1679-1754) and 
the Swiss jurist Emerich de Vattel (1714-67), both of whom attempted to develop an approach 
that avoided the extremes of each school.These new writings also focused greater 
attention on the law of peace and the conduct of interstate relations than on the law of war, as 
the focus of international law shifted away from the conditions necessary to justify the resort 
to force in order to deal with increasingly sophisticated interstate relations in areas such as the 
law of the sea and commercial treaties.The positivist school made use of the new scientific 
method and was in that respect consistent with the empiricist and inductive approach to 
philosophy that was then gaining acceptance in Europe.The former camp included the German jurist Samuel von Pufendorf (1632-94), 
who stressed the supremacy of the law of nature.