Italy also had a renowned philosophical movement in the 1800s, with Idealism, Sensism and Empiricism. The main Sensist Italian philosophers were Melchiorre Gioja and Gian Domenico Romagnosi. Criticism of the Sensist movement came from other philosophers such as Pasquale Galluppi (1770–1846), who affirmed that ''a priori'' relationships were synthetic. Antonio Rosmini, instead, was the founder of Italian Idealism. During the late 19th and 20th centuries, there were also several other movements which gained some form of popularity in Italy, such as Ontologism (whose main philosopher was Vincenzo Gioberti), anarchism, communism, socialism, futurism, fascism and Christian democracy. Giovanni Gentile and Benedetto Croce were two of the most significant 20th-century Idealist philosophers. Anarcho-communism first fully formed into its modern strain within the Italian section of the First International. Antonio Gramsci remains a relevant philosopher within Marxist and communist theory, credited with creating the theory of cultural hegemony. Italian philosophers were also influential in the development of the non-Marxist liberal socialism philosophy, including Carlo Rosselli, Norberto Bobbio, Piero Gobetti and Aldo Capitini. In the 1960s, many Italian left-wing activists adopted the anti-authoritarian pro-working class leftist theories that would become known as autonomism and ''operaismo''.