In the 1940s the Realist tradition reasserted itself, though divided between two different currents. The first of these was inaugurated by Citizen Kane and continued in the later films of Welles and Wyler. Its characteristic feature was the use of deep focus. By this means, the spatial unity of scenes could be maintained, episodes could be presented in their physical entirety. The second current was that of Italian Neo-realism, whose cause Bazin espoused with especial fervour. Above all, he admired Rossellini. In Neo-realism Bazin recognised fidelity to nature, to things as they were. Fiction was reduced to a minimum. Acting, location, incident: all were as natural as possible. Of Bicycle Thieves Bazin wrote that it was the first example of pure cinema. No more actors, no more plot, no more mise en scène: the perfect aesthetic illusion of reality. In fact, no more cinema. Thus the film could obtain radical purity only through its own annihilation. The mystical tone of this kind of argument reflects, of course, the curious admixture of Catholicism and Existentialism which had formed Bazin. Yet it also develops logically from an aesthetic which stresses the passivity of the natural world rather than the agency of the human mind.