By Level 3 you will be familiar with the idea that children are ‘socialised’ in the sense that they have to learn what is true, acceptable and normal within their society at a given time and place. Once they learn the rules they internalise them and think of them as ‘natural’. That is the way things are and ought to be.
There are many agents of socialisation, including comics, films and novels.
Students of literature will be familiar with idea of genre. Any novel will tell a story using certain literary conventions and will also assume certain social norms and values to be natural. It might be critical of some aspects of society (like Dickens and his sympathy for the poor) but other aspects will be unquestioned (e.g. the right of some individuals to be better off than others so long as they give the poor a bit of charity from time to time).
Barthes, in Writing Degree Zero (1953) argued that a given style of writing, even though we may see it as ‘natural’, is in fact developed in a particular time and place, It is chosen, and it reflects a certain ideology. The classical French style of writing made ‘bourgeois’ values seem natural. If we accept the style, we accept the values. This may be a matter of tone, vocabulary, or stylistic devices.
Modern writing (since and including Joyce, Becket, Proust etc) often draws attention to the very activity of writing. The text might actually remind you as part of its ‘message’ that it was made by a writer and read by a reader, so together we are creating a world. But even here, language can have an anaesthetic function. It not only reinforces certain values but makes things familiar to us so we stop having to think about them.
If you wished to push a particular political point of view, it is immensely helpful to have a set of films and novels and jokes supporting your values and perspective. It may be easier to start wars if the population is addicted to war films and war games on their I-pads. If lots of cops-and-robbers films persuade the audience the world is very dangerous and we need strong policemen to protect us, we are more likely to vote for increased powers for the police. In the seventies the audience usually knew who was guilty in the opening shots, as they saw the crime committed, but the police hero needed to prove it. They sometimes bents the rules to get proof, with a good measure of physical violence, but we knew who was guilty so that was OK. That plot model is now less popular. Instead, we have got used to false trails where everybody thinks they know who is guilty but often turn out to be wrong. We are learning to question evidence, as an audience and thus as a citizen.