In the decades around 1700 profane natural law developed an impact that can hardly be overestimated. Initially most clearly observable in the domain of practical philosophy, it ultimately spread far beyond this to make itself felt in areas as diverse as the theory of absolute rule and manuals for correct behaviour in everyday situations. The study shows how a social ethics and theory of duty based on natural law left its mark on various genres of moralist literature (moralist journals, satire, didactic literature, novels) between 1670 and 1770.