Priestley was a socialist, he expresses his opinions through the inspector and uses him as a mouthpiece. His views oppose those of Arthur Birling, Priestley sets the play in 1912, just before the titanic sank and both wars, Arthur said how he thought neither of those things would happen but the people watching the play would know he was wrong. This would enable people to more easily recognise that he would be wrong about other things as well, such as his views about lower classes being less important, which Priestley was against.
