Ishmael in many ways functions as a foil to Ahab, with his acceptance of the limits of his own knowledge and power in the world contrasting Ahab’s belief in his own ultimate power and ability to overcome nature. Readers can see this reflected in the different roles the two characters play, with Ahab’s dominance gaining extra emphasis from its contrast to Ishmael’s humility. While Ahab is shown to be a dictating and domineering commander, Ishmael’s role as a crew member is mostly marginal. While Ishmael is content to follow the action and accepts that he does not have full control, Ahab is always determined to lead, believing that if he tries hard enough he'll be able to gain control over his own narrative.
This difference is exemplified in the characters’ opposing approaches to the mysteries of life. While Ishmael can appreciate life’s mysteries for what they are, Ahab is determined to solve and master them. We can see this in the chapter entitled “The Sphynx,” in which the beheading of a hunted whale is detailed. While both Ishmael and Ahab acknowledge the whale’s head as a symbol of power and mysticism, where Ishmael can respect this mystery as beyond his understanding—his reference to it as the ‘sphynx’, for example, acknowledges its riddled enigma—Ahab demands an answer. “Speak, thou vast and venerable head” and “tell us the secret that is in thee,” he says. Where the mysteries of the world intrigue Ishmael, Ahab is left only frustrated at its exposure of his shortcomings.
Starbuck’s pragmatism functions as a foil for Ahab’s impulsiveness, and this emphasizes the irrationality of Ahab’s drive for vengeance. Stubb introduces Starbuck by saying that he's “as careful a man as you’ll find anywhere in this fishery,” thus immediately bestowing him with a reputation for caution and sense. Ishmael goes on to describe Starbuck’s attitude towards whaling by saying:
He had no fancy for lowering for whales after sun-down; nor for persisting in fighting a fish that too much persisted in fighting him. For, thought Starbuck, I am here in this critical ocean to kill whales for my living, and not to be killed by them for theirs.
Here, Starbuck’s pragmatism is made clear: he is a man who will fight when he thinks he can win, but he won't push his luck. This cool rationality stands in stark contrast to Ahab, who is hotheaded and eager to fight. This contrast in their natures comes to its zenith in their opposing views towards pursuing Moby Dick. While Ahab makes clear his will to pursue Moby Dick whatever the cost, Starbuck stands as the voice of reason, pleading with Ahab to stop in his heedless quest, which he recognizes can only lead to all of their ruins. After Ahab reveals the real mission that the Pequod has set out on (which has to do with his personal vengeance for Moby Dick), Starbuck draws attention to the irrationality of this quest, saying: “Vengeance on a dumb brute! [...] that simply smote thee from blindest instinct! Madness! To be enraged with a dumb thing, Captain Ahab, seems blasphemous.” Starbuck’s emphasis on the whale as a “dumb brute” that acts from “instinct” shows a distinctly different worldview to Ahab, who views Moby Dick as a creature with the same capacity to feel and act as he himself has. While Starbuck is able to view things through an impartial, objective lens, Ahab’s ego means he views things with a distinctly personal edge. Accordingly, Moby Dick’s dismembering of him was not merely an urge of instinct, but a measured and targeted act that warrants personal revenge. Starbuck’s objection that Ahab’s anger seems “blasphemous” also highlights the religious aspect to this character foil, with Starbuck’s piousness standing in stark contrast to Ahab’s heathenism. Ahab, after all, explicitly baptizes his mission in the name of the devil, underscoring just how thoroughly his worldview contrasts Starbuck's religious beliefs.
Starbuck’s pragmatism functions as a foil for Ahab’s impulsiveness, and this emphasizes the irrationality of Ahab’s drive for vengeance. Stubb introduces Starbuck by saying that he's “as careful a man as you’ll find anywhere in this fishery,” thus immediately bestowing him with a reputation for caution and sense. Ishmael goes on to describe Starbuck’s attitude towards whaling by saying:
He had no fancy for lowering for whales after sun-down; nor for persisting in fighting a fish that too much persisted in fighting him. For, thought Starbuck, I am here in this critical ocean to kill whales for my living, and not to be killed by them for theirs.
Here, Starbuck’s pragmatism is made clear: he is a man who will fight when he thinks he can win, but he won't push his luck. This cool rationality stands in stark contrast to Ahab, who is hotheaded and eager to fight. This contrast in their natures comes to its zenith in their opposing views towards pursuing Moby Dick. While Ahab makes clear his will to pursue Moby Dick whatever the cost, Starbuck stands as the voice of reason, pleading with Ahab to stop in his heedless quest, which he recognizes can only lead to all of their ruins. After Ahab reveals the real mission that the Pequod has set out on (which has to do with his personal vengeance for Moby Dick), Starbuck draws attention to the irrationality of this quest, saying: “Vengeance on a dumb brute! [...] that simply smote thee from blindest instinct! Madness! To be enraged with a dumb thing, Captain Ahab, seems blasphemous.” Starbuck’s emphasis on the whale as a “dumb brute” that acts from “instinct” shows a distinctly different worldview to Ahab, who views Moby Dick as a creature with the same capacity to feel and act as he himself has. While Starbuck is able to view things through an impartial, objective lens, Ahab’s ego means he views things with a distinctly personal edge. Accordingly, Moby Dick’s dismembering of him was not merely an urge of instinct, but a measured and targeted act that warrants personal revenge. Starbuck’s objection that Ahab’s anger seems “blasphemous” also highlights the religious aspect to this character foil, with Starbuck’s piousness standing in stark contrast to Ahab’s heathenism. Ahab, after all, explicitly baptizes his mission in the name of the devil, underscoring just how thoroughly his worldview contrasts Starbuck's religious beliefs.
Captain Boomer, who has lost his arm to Moby Dick, functions as a foil to Ahab because he responds to his own dismemberment much differently than Ahab responds. The fact that one lost a leg and the other an arm to Moby Dick clearly spotlights Melville's desire to present Ahab and Boomer as mirror images of each other.
By emphasizing their similarities, Melville is subsequently able to make their differences appear even more stark, most notably in their contrasting responses to their dismemberment. While the loss of his leg to Moby Dick leaves Ahab determined to seek vengeance, Boomer shows an alternative response. Asked whether he has come across Moby Dick again since losing his arm, Boomer says he has twice but has never attempted to strike him again. He explains:
“He’s welcome to the arm he has, since I can’t help it, and didn’t know him then; but not to another one. No more White Whales for me; I’ve lowered for him once, and that has satisfied me. [...] he’s best let alone; don’t you think so, Captain?”—glancing at the ivory leg.
Here, Boomer’s response to his dismemberment shows him to be far more rational and pragmatic than Ahab. He's happy to cut his losses and not risk losing anything else. Indeed, in describing his encounter with the White Whale, Boomer talks about his gratitude to have just lost his arm when he could have easily lost his life. By contrast, Ahab’s dismemberment by Moby Dick leaves him bitter and full of rage, clearly seeing the act as a personal affront that must be avenged. Ahab’s encounter with Moby Dick has in no way left him “satisfied” like Boomer. To the contrary, Ahab is unable to rest until he has hunted down Moby Dick again. Boomer’s measured explanation of his decision to move on from hunting White Whales works to highlight the absurdity of Ahab’s personal vendetta against Moby Dick.