The specific part in an area of emphasis to which the viewer’s eye is drawn is called a focal point.
I WISH YOU HAPPINESS EVERY DAY TOO :)
Basically to Ahab there exists something more behind the world some kind of neo-Platonic aspect. He thinks there is an unknown reasoning behind the mask of all visible things, what that is can be any man's guess but to Ahab whatever it is, it is nothing less then vengeful.
