In the post-classical West, with the influence of Christianity, language studies were undermined by the naïve attempt to derive all languages from Hebrew since the time of Saint Augustine. Prior studies classified the European languages as Japhetic. One of the first scholars to challenge the idea of a Hebrew root to the languages of Europe was Joseph Scaliger (1540–1609). He identified Greek, Germanic, Romance and Slavic language groups by comparing the word for "God" in various European languages. In 1710, Leibniz applied ideas of gradualism and uniformitarianism to linguistics in a short essay. Like Scaliger, he rejected a Hebrew root, but also rejected the idea of unrelated language groups and considered them all to have a common source.