The roots of Italian idealism are to be found in the work of Giambattista Vico (1668–1744), professor of Latin Eloquence at the University of Naples. Years before Hegel's Phenomenology of Spirit (1807), Vico's New Science (1725) conceived of knowledge as acquired through a self-generative process. To Vico, thought in its development is first ‘poetic wisdom’ then becomes understanding and finally achieves unity of truth and certainty. Thought here does not merely represent, but actively creates reality. It is, moreover, conscious of its own generative process (verum et factum convertuntur).

Vico's epistemological idealism is bolstered by a religious metaphysics which postulates the unity of human thought with divine thought. The ‘common sense’ (sensus communis) of humanity, which orders the social and historical world is thus also identical with divine providence, and this identity acts to verify or ground the knowledge engendered by human thought.

Vico's ideas, however, won little recognition at the time. Thus the revival of idealism in Italy at the University of Naples, dating from 1840, was initially focused on Hegel, rather than Vico. The result was a Neapolitan school of Hegelianism. For A. Vera, leader of the ‘orthodox Hegelians’ at Naples, thought represented the ‘absolute idea’ in Hegelian terminology, which stood outside of human control. But two other central figures in Neapolitan Hegelianism, B. Spaventa (1813–83) and F. De Sanctis (1817–83), rejected this transcendence. Connecting Vico (whom they had rediscovered) to Hegelianism, Spaventa and De Sanctis defended a radical humanism that located all truth and reality solely in this world.