It'd be easy to say that Bartholomew and the Oobleck is just about the power of an apology. Why? Because that's the quickest thing to spot. After all, the oobleck won't go away until the King realizes he's messed things up to a royal degree and that he should make up for it in a way that's truly regal. Or maybe it's about sticking to your moral convictions. You know, not backing down when a stronger voice shouts back.
But as for apologies and convictions, how far can they really stretch? And let's give Dr. Seuss some credit here. The man is a master storyteller with a PhD in More Than Meets the Eye. If that oobleck was in a repressed emotions and themes contest with Betty Draper, the oobleck would win—hands down.