the frankfurt school is often described as combining marxism and freudianism, a strategy that remains alive in the acdemic world, for example in the work of terry eagleton. maybe there is a piece of marcuse or adorno where they work that out carefully on the meta-level. but really you should ponder this combination, for it makes no sense. and at its worst, as in eagleton, it just kind of randomly leaps between orthodoxies that are obviously incompatible with one another. you might as well make it marx and locke, or freud and skinner. lacan and althusser aren't going to help at all, i believe, even if you're zizek. what is the nature of the unconscious, according to marxism, and how does it bear on politics and economics? so say we spend the next twenty years exploring my childhood traumas, my anal phase, all the mythological narratives and complexes that constitute my self, my dreams, and so on. what, according to marx, have we accomplished? on the other hand, what is the role of class structure and material conditions of production in the thought of freud? i think you could regard these both as interesting or historically important movements of thought (i do regard them that way; also as completely over, thank god), but tossing them like bouillabaisse and marshmallow fluff into the same food processor and hitting puree is not going to leave you with a good meal. i guess you could toss in nietzsche...wait, just stop.