Also, notice how Sheila and Eric are affected by it and start to change their views? That wasn't change, it was part of their conscience all along, but it took a direct confrontation with their consciences in the form of Inspector Goole to realise it. Mr Birling, Mrs Birling and Gerald, on the other hand genuinely believe that they had nothing to do with it and weren't responsible, and therefore were not affected.Inspector Ghoul (as we`re going to call him for now) killed the inspector and ate him. He then read Eva`s diary, and in a flood of pity for her went off to torment the family who led to her suicide in the form of the murdered inspector. The policeman who arrived later was the actual investigator who found Eva`s corpse and diary.
- As Gerald points out, Goole very carefully only showed the photo to one of them at a time, and they only have his word for it that these were all the same girl. Eva Smith, the girl at the clothing store, Daisy Remington, Sarah, and the girl Mrs Birling turned down could have all been five different girls (though the fact that the pregnant girl gave her name as "Mrs. Birling" does imply that she was Sarah, so more likely there were four girls). Only one of them (most likely Sarah/the pregnant girl) committed suicide that night, but Goole decided to take the opportunity to call all the Birlings to account for the various lives they'd harmed.