Lon Luvois Fuller (June 15, 1902 – April 8, 1978) was a noted legal philosopher, who wrote The Morality of Law in 1964. Fuller was professor of Law at Harvard University for many years, and is noted in American law for his contributions to the law of contracts. His debate with H. L. A. Hart in the Harvard Law Review (Vol. 71) was important in framing the modern conflict between legal positivism and natural law. Fuller was an important influence on Ronald Dworkin, who was one of his students at Harvard Law School.