The play has a theme of dramatic irony, when Birling talks of the Titanic claiming that she was unsinkable when in fact she sank on her maiden voyage a week later, Priestley does this to show that no matter how much Birling thinks he is right he can be wrong. He does this with the Titanic so that the audience will instantly pick up on it and realise what he is saying isn’t all true, even though he thinks it is. The author J. B Priestley was brought up in a socialist way so he based all his negative opinions of capitalism upon Birling character.
This was done to that Priestley could get his point across how to stop wars and fights from happening. In the time that the play was set it was a patriarchal society; Sheila shows this in the play after her mother questions where Gerald was the previous summer during the 1912 men were never questioned by women. This way of thinking would add to the self importance of Birling character as he would have expected to be looked up to by the rest of his family.
The Inspector’s role in this play is to show how one person can bring out all the Seven Deadly Sins in the characters which he is interviewing drawing a comparison to the original morality plays of the late middles ages but showing a much more modern view which the audiences of post war Britain would relate to. The contrast between Sheila and Eric, Birling’s children with Birling himself shows that they are trying to be themselves not what Birling wants them to be.
He criticises Sheila’s choice of words when she describes Eric as ‘squiffy’ at the beginning of the play saying ‘the things you girls pick up these days’. He then shows a difference between Eric and Birling when Eric says that he would not have sacked Eva Smith for asking for more money telling his son that he should learn a few more responsibilities. Birling clearly feels that there is a difference between his views and those of his son and daughter and Priestley shows this in these ways.