He thus posed the philosophical problem of Marx's evolution as the question of how may one conceive the transformation of Marx's thought without adopting an idealist perspective which would mark a return to Georg Wilhelm Friedrich Hegel's spiritualist dialectics and its teleological perspective (the hen is in the egg as mature Marx would be in the young Marx, the "contents" of his dialectical materialist philosophy expressed in his earlier works under the "words" of Feuerbach's idealism). The theory prominent in the "Manuscripts" is a "return to species-essence" - a normative, anthropological theory. Some commentators suggest that the later Marx abandons this idea in favour of a structural description. Sidney Hook, Daniel Bell and Lewis Feuer hold that the change in mode of exposition in Marx's "Capital" corresponds to a change in his ideas. Jean-Yves Calvez, Robert C. Tucker, David McLellan, Iring Fetscher and Shlomo Avineri deny this is the case. Siegfried Landshut, Heinrich Popitz, A. G. Meyer and Erich Fromm hold that the theory of the early Marx is richer than the more restricted theory of the later Marx. Commentators such as Benedetto Croce, Karl Löwith and Sidney Hook argue that the later Marx also abandons Hegelianism completely, a view disparaged by György Lukács, Iring Fetscher, Robert C. Tucker and Shlomo Avineri. Ernest Mandel distinguishes three different positions in this regard:  Vladimir Lenin claimed Marx's first mature work as "The Poverty of Philosophy" (1847) in his own work "State and Revolution" (1917). Althusser, who was a champion of this young–mature dichotomy in his criticisms of Marxist humanism (Praxis School, John Lewis and the like) and existential Marxism, claimed in the 1960s that "The German Ideology" (written in 1845), in which Marx criticized Bruno Bauer, Max Stirner and other Young Hegelians, marked the break with this young Marx. Furthermore, the Trotskyist Ernest Mandel in his "The Place of Marxism in History" (1986) also broke Marx's intellectual development into several different stages. Althusser presented, in his "For Marx" (1965), a number of other opinions:   Althusser popularized the conception of an "epistemological break" between the Young Marx and the mature Marx, that is the point where Marx broke with ideology to enter the domain of science, a point generally considered to consist in his break with Ludwig Feuerbach.