Answer: Ahab has lost his sanity but is still determined to have his revenge.
Step-by-step explanation:
The meaning of this excerpt is that Ahab has become totally crazy but this craziness fuels him to seek revenge. Inevitably,He has reached a point where he is as much a victim as he is an aggressor. The whale is the target of his fury and his mind is lost in the lunacy of his pursuit for revenge. He has reached a point of no return.