" Contrary to popular belief and hope, people don't usually come running when they hear a scream. That's not how humans work. Humans look at other humans and say, 'Did you hear a scream?' because the first scream might have been you screaming inside your head, or a horse backfiring. "

― Terry Pratchett , Unseen Academicals (Discworld, #37; Rincewind #8)