Captain Ahab’s white whale is a metaphorical object for the ages. When it comes to In the Heart of the Sea, Ron Howard’s soggy nautical epic, an unconvincing take on the Moby Dick myth, the sea monster invites symbolic interpretations too tempting to ignore. Maybe Ahab’s desperate, pointless chase for the creature represents Howard’s search, now 23 features in, for a distinctive style or personality? Maybe the good ship Essex, our seafaring vessel for most of the two-hour run, is a stand-in for the movie, drifting through the endless blue, its maps and compasses pointing towards an ever-receding point or point of view? Or maybe the movie is the…