What persuades men and women to mistake each other from time to time for gods or vermin is ideology. One can… — Terry Eagleton

It follows that through its constitution ideology is involved in the functioning of this social-imaginary relation, and is therefore necessarily false; its social function is not to give agents a true knowledge of the social structure but simply to insert them as it were into their practical activities supporting this structure. Precisely because it is determined by its structure, at the level of experience the social whole remains opaque to the agents. In class-divided societies this opacity is over-determined by class exploitation and by the forms which this exploitation takes in order to be able to function in the social whole. Hence, even if it includes elements of knowledge, ideology necessarily manifests an adequation / inadequation vis-à-vis the real.

Ideology consist of a specific objective level, of a relatively coherent ensemble of representations, values and beliefs: just as 'men', the agents within a formation, participate in an economic and political activity, they also participate in religious, moral, aesthetic and philosophical activities. Ideology concerns the world in which men live, their relations to nature, to society, to other men and to their own activity including their own economic and political activity. The status of the ideological derives from the fact that it reflects the manner in which the agents of a formation, the bearers of its structures, live their conditions of existence; i.e. it reflects their relation to these conditions as it is 'lived' by them. Ideology is present to such an extent in all the agents' activities that it becomes indistinguishable from their lived experience. To this extent ideologies fix in a relatively coherent universe not only a real but also and imaginary relation: i.e. men's real relation to their conditions of existence in the form of an imaginary relation. This means that in the last analysis ideologies are related to human experience without being thereby reduced to a problematic of the subject—consciousness. This social-imaginary relation, which performs a real practical—social function, cannot be reduced to the problematic of alienation and false consciousness.

As opposed to science ideology has the precise function of hiding the real contradictions and of reconstituting on an imaginary level a relatively coherent discourse which serves as the horizon of agents' experience.