How is the theme of responsibility explored by J.B Priestley in 'An Inspector Calls'?

An Inspector Calls delves into the theme of responsibility - exploring which different demographics of individuals are willing to take responsibility for the death of Eva Smith. Priestley achieves this by creating binary oppositions of the reactions of characters dependent on their class or age. For example, as an elder character, Mrs Birling believes that the whole situation is 'impertinent' whereas the younger characters such as Sheila Birling are depicted as remorseful in 'if she had been some plain old creature, I don't suspect i'd have done it'. Here Priestley demonstrates that the 'younger ones are more impressionable' commenting on the differences in responsibility in age different generations in society.