People find our marxism inconsistant and our avant gardism passé. But just as an A rated investment can be made out of several B rated investments, a single valid genre can be made up out of these two discredited genres: historicism.
Historicism seeks to pin changes in consciousness to changes in the structure of society.
From marxism is borrowed the idea that social structures determine patterns of thought and the periodisation of history. From the theory of avant gardism (e.g. Hegel) comes the idea that history can be profitably considered as a series of avant garde movements that progressively succeed each other. Because they have a necessary relation to social structures, the particular mechanisms by which they develop out of these structures (which are obscure in any case) do not need to be given.
For instance, Simon Leys writes about a Chinese history of European philosophy, printed subsequent to the Cultural Revolution:
"the introduction of the class struggle into European philosophy turns that history into a shooting gallery where no one is spared"
Leys then translates part of the section on Nietzsche, which is meant to represent a particularly crass example of historicism:
"Nietzsche pursued and developed the esoteric voluntarism of Schopenhauer. He announces fascism. He publicly defended enterprises of cruel oppression and aggression launched by the reactionary-bourgeois class, having developed to the point where it could shed its democratic trappings, openly adopted a policy of violent dictatorship: it developed in the last part of the nineteenth century when capitalism was changing into imperialism"
In some ways this might be useful information if the reader were permitted to actually read Nietzsche. The major fault, by my reckoning, is treating a casual relationship between Nietzsche's writings and Imperial policy as a necessary one (in the pantheon of Nietzsche's muses Bismarck looms inordinately over Syphilis). But that's not really the point. The premises of historicism are necessarily faulty: material structures determine thought in ways too complex for us to understand; the periodisation of history is an exercise of taste; Hegel's avant gardism is second cousin to horse racing systems. The point is that history can be simplified to the point at which it becomes useful, acording to the necessarily unscientific application of the faculty of taste.