In his introduction to the play, Tom says that Jim is a symbol of
the long delayed but always expected something that we live for (scene 1)
In other words, Jim is not just a character; he also becomes the symbol of hope for the Wingfields, a goal to be achieved, an ideal to be realised. As a gentleman caller and hoped-for marriage partner for Laura, he represents Amanda’s hopes for her daughter’s future, which would also release Tom from some of his family responsibilities in having to materially provide for his sister. Jim becomes this symbol in Tom’s view, because Tom, a self-confessed poet, ‘has a weakness for symbols’ (scene 1).
Tom also describes Jim as
the most realistic character in the play, being an emissary from a world of reality that we were somehow set apart from (scene 1)
Here, Tom deliberately sets Jim in contrast to the only other characters in the play – the Wingfield family. Jim is part of the outer world, which the Wingfields are excluded from as it seems. Until he makes his appearance, the play is taken up with the self-enclosed, isolated family world of the Wingfields who spend most of their time in dreams and memories and longings. As a potential marriage partner for Laura, Jim can provide a permanent link between their isolated world and society at large.
However, at a closer glance it might appear that Jim is not so terribly different from the Wingfields after all. He is confident and self-assured, but he has not really progressed very far in society either; he works at the same warehouse as Tom, albeit at a slightly higher level. And he too lives in some kind of illusion, about
what the future will be in America, even more wonderful than the present time is! (scene 7).
In view of his own situation and the general economic depression of the times, not to mention the ever-looming threat of world war, this assessment appears extremely optimistic to say the least. And instead of becoming the means by which the Wingfields can escape their seclusion, he unwittingly shatters their hopes as, being already engaged, he is unable to start dating Laura.