lonely for something you can't name

Hal's Pump-Room abstraction is the whole theme compressed to a sentence: a loneliness with no locatable object, missing "somebody he's never even met," an ache for a connection that was never had and can't be named. It universalizes the failure-to-connect out of any single scene into the book's ground condition — the self homesick for a contact it has no memory of and no address for, which is exactly why the feeling "would make no sense" without being made general.