In these last two columns I want to bring us back to more speculative, philosophical and even theological ground with a discussion of ideology and of alienation. I will cover the concepts in Marx and his immediate successors and will then go on to talk about the way in which "western" Marxism evolved out of the failure of the much-heralded proletarian revolutions of the 19th century and the turn towards moderate "social democracy", the rise of fascism in the inter-war period and the descent of Soviet Marxism into reductionist barbarism. All of these developments run counter to what Marxists had largely hoped and worked for until the first world war. What Marxist thinkers since Marx have been wrestling with is the question as to why nothing unfolded as it should have done.

Marx maintains that the ruling ideology is always the ideology of the ruling class and that the set of ideas and thought patterns existing in any epoch will – "in the final instance" – closely follow the material and social relations of production. As soon as the surplus product we have been discussing emerges and class develops which has control over that surplus, then that class will require that those who do the producing learn to accept the "rules" of production and distribution.

Thus, in feudal society, for example, we will have feudal ideologies that emphasise hierarchy, God-given positions in society, stability and the divine right of kings to rule and a religious form that bolsters those requirements – in European feudalism this is represented by Catholicism and orthodoxy.

The order that prevails will always be seen for extended periods of time as the "natural law" in which the way things are is the way they should be. In bourgeois society the rules change. Stasis and hierarchy are overthrown in the name of dynamism and innovation and a breaking down of restrictive practices and you become a "self-made man" off to seek your fortune. In religious terms, orthodox Catholicism is superceded by a religion that allows you to find your personal relationship with God, or in Engels' terms, become functionally secular.

Where once the divine right of kings was seen as the natural law, it now becomes unnatural because it is surplus to requirements and is superceded by the human right to remove the head of the king if necessary. So, the rules may change, but they still have to be learned. However, this learning of the rules is not done merely by repression (although this becomes necessary at times of upheaval) but by the gradual inculcation of values.

Althusser, for example, describes these two functions as repressive and ideological state apparatuses. The former is clear, but the latter is far more insidious. It is the way in which the prevailing rules of the game become second nature to you and your obligations are turned into your desires. Antonio Gramsci similarly described this dichotomy in terms of domination and hegemony. What this means at base is that the ideas we have about society are not actually our own but are put there by a set of institutions that have convinced us there is no other way to think about the world, that it is as it must be.

Perhaps an unusual way of understanding this is through Kafka's Metamorphosis, perhaps the most famous account ever written of a man who has turned into a beetle overnight. But the real strangeness of the story is not the fact of the physical transformation (after all, he has been a bug all his working life and reality is just catching up with psychology) but of what it represents. At one point Gregor Samsa says of his family and his work life:

"The fruits of his labour were transformed into the provision of money ... and he earned enough to meet the expenses of the entire family and actually did so. They had just become used to it, the family as well as Gregor, the money was received with thanks and given with pleasure, but that special warmth was missing."

If this isn't Kafka's spin on Marx's line from the Communist Manifesto that "The bourgeoisie has torn away from the family its sentimental veil, and has reduced the family relation into a mere money relation" then I don't know what is. Gregor's metamorphosis into a bug is the outward and inward transformation of the need to earn money into his own picture of himself. This is alienation theory in a beetleshell. It is not that he was poor and therefore suffering and needed to be kept down by a police state, but that the necessity of having to work for others at a job he hates for an amorphous output which doesn't belong to him alienates him from himself and from his labour power. Kafka's power as a writer lies in the fact that he shows us characters who have no concept of what is being done to them as a result of their own alienation. Gregor's absorption of bourgeois values means that when he wakes, all he can think of is that he is going to be late for work and not that he has turned into a bug.

What happens in 20th century western Marxism is that a Marxist interpretation of socio-economic development is increasingly complemented by this attempt to incorporate a psychological understanding of the way people function in the world. Marx gets married to Freud with Kafka as the best man and the result is the pitter-patter of the tiny little feet of Adorno, Horkheimer, Marcuse, Korsch, Lukacs, Benjamin, Bloch, and later Žižek and the other post-Marxists, all of whose voices we will listen to next week.