The idea of life being a play forms an extended metaphor throughout Moby-Dick and reflects man’s inability to fight his own fate. This metaphor also asserts the power of art. Ishmael introduces the metaphor in the very first chapter:
Though I cannot tell why it was exactly that those stage managers, the Fates, put me down for this shabby part of a whaling voyage, when others were set down for magnificent parts in high tragedies, and short and easy parts in genteel comedies [...] yet, now that I recall all the circumstances, I think I can see a little into the springs and motives which being cunningly presented to me under various disguises, induced me to set about performing the part I did, besides cajoling me into the delusion that it was a choice resulting from my own unbiased freewill and discriminating judgment.
Here, Ishmael sets forth the idea that all men are like characters in a play, cast for their role by the Fates and unable to control their own narrative. His reflection on the cunning involved in this, with the stagecraft so effective that one can barely detect its machinations, speaks to the ease with which humans can delude themselves that they act by their own will and reinforces the determinative role of fate in the novel.
The comparison of the Fates (an allusion to the three ancient Greek sister deities who functioned as the personification of destiny) to “stage managers” proves significant in the way it characterizes artists as possessing their own quasi-divine power. Just as the Fates appoint Ishmael’s “shabby part of a whaling voyage,” so too does the playwright play god in his art, having the ultimate power to choose the destiny of the characters. This metaphor naturally has metatextual implications on the construction of Moby-Dick itself, with this point reflecting Ishmael’s own power over the events of the novel. That some of the chapters are even written in the form of a play (complete with stage directions) reinforces this implication, as Ishmael effectively serves as the Fates in Moby-Dick.
In the chapter “Cetology,” Ishmael classifies whales through an extended metaphor that systematizes whales as different books and folios. Explaining the “grand divisions of the entire whale host,” Ishmael breaks the species down into three primary books, subdivisible into chapters, referred to as the “folio whale,” the “octavo whale,” and the “duodecimo whale.” Here, Ishmael borrows terms from printing, with folios, octavos, and duodecimos all types of book format, distinct by their variation in size.
The use of a printing analogy to classify the whales reflects the importance of books as a source of processing knowledge, an emphasis that draws attention to the purpose of Moby-Dick itself, which can also be seen as an attempt by Ishmael to distill and understand the world around him. Indeed, Ishmael proves obsessed with the collation of knowledge, with the novel largely used by him as a way to organize and process what he accumulates. The contents of Moby-Dick highlight Ishmael’s determination to accumulate and systematize knowledge.
Ishmael’s systematization can be seen as a response to the overwhelming nature of knowledge; the division of different books and chapters is an attempt to impose order. Indeed, when outlining his method of dividing up the species, Ishmael expresses how it is a response to the otherwise “harbourless immensities” of the subject matter. Ishmael’s attempt at what he calls “the classification of the constituents of chaos” is thus an attempt to find his way through the chaos through imposing order and definitions. His choice to do so with a metaphor that focuses on books hints at how this is also the purpose of writing itself, with the novel ultimately serving as an attempt to make sense of the world through the use of language and structure.
In his soliloquoy in Chapter 37, Ahab metaphorically suggests that his will is so focused and unchanging that it runs along "iron rails" like a train:
Swerve me? The path to my fixed purpose is laid with iron rails, whereon my soul is grooved to run. Over unsounded gorges, through the rifled hearts of mountains, under torrents’ beds, unerringly I rush! Naught’s an obstacle, naught’s an angle to the iron way!
Ahab paints an evocative image of his soul being grooved to run along an iron track. In turn, he sheds light on the rigidity of his fate. The reference to iron rails alludes to the novel’s industrial context, in which the distinction between humans and machine has become a significant philosophical discussion as peoples’ lives become increasingly dictated by the needs of industrial capitalism. Ahab’s association of his soul with iron speaks to this, invoking the idea of humans running as machines. The symbolism of Ahab's prosthetic leg, which blends the natural and manufactured, may also nod to this concept. Earlier in his soliloquy, Ahab also refers to the heaviness and jaggedness of the “Iron Crown” he wears—imagery that represents the hardiness and toil that comes with the successes of industrialism.
In Moby-Dick, Melville uses the “formal whaling code” of "Fast-Fish" and "Loose-Fish" as a satirical metaphor for colonialism and slavery that aims to expose the absurdity of politics at the time. Ishmael explains that the whole whaling code can be boiled down to two principles, and he goes on to argue that in these two laws can “be found the fundamentals of all human jurisprudence” (that is, the fundamentals of the law). These laws are:
I. A Fast-Fish belongs to the party fast to it.
II. A Loose-Fish is fair game for anybody who can soonest catch it.
Through this metaphor, Ishmael explains how if a whale is loose it is fair game. But if someone else is “fast” to a whale (that is, attached with their harpoon), you must respect their ownership. Ishmael emphasizes the comprehensiveness and absoluteness of these rules in an intentionally comic way. He explains a case debated in court, for example, where one party chases and harpoons a whale, but then abandons their line in order to save their lives. When another party then shortly thereafter kills the whale in front of the first party, the harpoons and lines rightfully transfer to their ownership, with the whale having “acquired a property in those articles” for itself. When claimed by another, these articles thus transfer to their ownership, too. Through this example, Ishmael highlights some of the potential injustices of the principle while also describing it in a way that is intentionally absurd, with the idea that a whale can acquire property for itself, for example, seeming intentionally satirical.
Furthermore, Ishmael goes on to explain how these rules may be applied to the whole of human jurisprudence, using "Fast-Fish" and "Loose-Fish" as a metaphor to describe other worldly affairs:
Is it not a saying in every one’s mouth, Possession is half of the law: that is, regardless of how the thing came into possession? But often possession is the whole of the law. What are the sinews and souls of Russian serfs and Republican slaves but Fast-Fish, whereof possession is the whole of the law? [...] What was America in 1492 but a Loose-Fish, in which Columbus struck the Spanish standard by way of waifing it for his royal master and mistress? [...] What is the great globe itself but a Loose-Fish? And what are you, reader, but a Loose-Fish and a Fast-Fish, too?
Here, Melville powerfully portrays how the whole of contemporary politics and global power dynamics is dictated by this very same notion of property, a notion that is as primitive as laying claim to something because you have put a stick in it. Ishmael’s examples, which encompass Russian serfs, Republican slaves, and the colonization of America itself, clearly seek to make a point about contemporary politics and the injustices of slavery and colonialism. The reminder that possession is half or even the whole of the law “regardless of how the thing came into possession” is a clear invocation of the bloody and unjust ways in which things often come to be one’s "property." The final address to readers, which reminds them that they are “but a Loose-Fish and a Fast-Fish, too,” highlights man’s own vulnerability to this system, in which their own lives may just as easily be laid claim to. Through this metaphor, Melville thus satirizes contemporary notions of property, showing how modern civilization is really much more primitive than it may think itself to be.
When describing Queequeg’s tattoos, Ishmael uses a metaphor that refers to Queequeg’s body as “living parchment” on which is written an unreadable riddle. When Queequeg is carving the coffin with copies of his tattoos, Ishmael explains how Queequeg got his tattoos:
And this tattooing had been the work of a departed prophet and seer of his island, who, by those hieroglyphic marks, had written out on his body a complete theory of the heavens and the earth, and a mystical treatise on the art of attaining truth; so that Queequeg in his own proper person was a riddle to unfold; a wondrous work in one volume; but whose mysteries not even himself could read, though his own live heart beat against them; and these mysteries were therefore destined in the end to moulder away with the living parchment whereon they were inscribed, and so be unsolved to the last.
Ishmael’s comparison of Queequeg to a “riddle to unfold” reflects his struggle to ever fully understand Queequeg. Ishmael enshrouds Queequeg in enigma from the beginning of the novel. Significantly, Queequeg is a character who barely uses his voice, speaking only about a dozen times in the novel. And when he does speak, he uses broken English, a fact that reflects his mystery for Ishmael, for whom he is a largely unreadable character. That the tattoos are told to contain “a complete theory of the heavens and the earth” and a “mystical treatise of the art of attaining truth” emphasizes the sense of mystery surrounding Queequeg, with Ishmael’s struggle to comprehend Queequeg representing his larger struggle to obtain meaning and truth.
The association of Queequeg with writing—with his skin described as “living parchment” and his body “a wondrous work in one volume”—also has metatextual implications. This is not the only time Ishmael uses books as a metaphor in such a way. His chapter on cetology, for instance, uses a similar metaphor to compare whales (another symbol of mystery) to books and folios. Books and writing thus come to be symbolic of Ishmael’s attempt to grapple with life’s mysteries. Writing, in other words, becomes an act of imposing order on an otherwise chaotic, unknowable world.
Furthermore, Queequeg’s tattoos also come to be a symbol of the ways language can counter mortality. While Ishmael reflects that the mysteries inscribed on Queequeg’s body were “destined in the end to moulder away” with his death, it is also apparent to the reader in the very act of reading this passage that this is not the case. Not only has Queequeg gone on to inscribe these mysteries onto the coffin, an object that will outlast himself, but Ishmael’s writing of this passage can also be seen to represent a way of transmitting these mysteries. While the inscriptions remain incomprehensible, the way in which they are continually reproduced and transmitted speaks to the immortalizing power of language and the written word.
In the penultimate chapter, one of the closing images the reader is left with is the metaphor of the sea as a shroud. After the Pequod and its crew is sunk, Ishmael writes:
Now small fowls flew screaming over the yet yawning gulf; a sullen white surf beat against its steep sides; then all collapsed, and the great shroud of the sea rolled on as it rolled five thousand years ago.
The comparison of the sea to a great shroud (a cloth placed around a dead body for burial) creates a powerful image that invokes the ultimate power of nature over man. The comparison of the sea to a shroud reinforces the novel’s frequent association of the sea with death, an association that harks back to the very first chapter, in which Ishmael compares his draw to the sea with an act of suicide. The metaphor’s emphasis on magnitude, with the sea able to envelop the whole vastness of the ship, emphasizes man’s smallness in the face of nature. This is further reinforced by the stress on the constancy and timelessness of this power, with the sea rolling on as did “five thousand years ago.” Together, these elements of magnitude and timelessness work to emphasize the universality that the metaphor wants to portray.
The double meaning of a shroud, which refers both specifically to the funeral garment but also more figuratively to just something that obscures, is also apt, with the latter alluding to the sea’s (and death’s) power to erase. The sinking of the ship not only represents the deaths of the shipmates, but also the burial of their stories, with all evidence of their existence lost to the sea. While their memory will live on in Ishmael’s tale, the use of the shroud metaphor may be a way of hinting at the imperfections of this tale, since it will only ever unveil partial truths. The complete tale of the Pequod, like its occupants, lies buried at the bottom of the sea.