Once there was a hippo.  This hippo was very special, for no other reason than the fact that it had no special qualities at all.  And because it was named Samuel.  On a typical day, Samuel would eat, and eat, and eat some more, until his bloated belly could handle no more fish.  But this wasn't a typical day.  Today his belly could handle more fish, because he didn't eat as much as he usually does.  He might be sad.  Yeah, I bet that's why he didn't eat so much.