It is not unusual for a non-bookman, upon entering the book-lined domicile of a bookman, to crack, "Have you read them all?" The quip smacks of a veiled accusation of hypocrisy, the suggestion being that the bookman is making a false show of an erudition and well-readedness the likes of which he does not possess. I invariably reply, "This is no show library, this is a working library." That tends to shut 'em up.
A nephew gave me a coffee cup inscribed thusly: "A room without books is like a body without a soul." The attribution was to Cicero, but one learns to take such attributions cum grano salis. Whatever the quotation's source, it sums up the matter well.