Two Great Heads Side by Side
Chapter 74 of Moby-Dick opens with Ishmael inviting the reader to study the two whale heads now hanging from opposite sides of the Pequod. He declares the Sperm Whale and the Right Whale the only two species regularly hunted by man, and notes that their external differences are most observable in their heads. The Sperm Whale's head possesses a "certain mathematical symmetry" that the Right Whale's sadly lacks, and its pepper-and-salt coloring at the summit marks it as a "grey-headed whale" of advanced age and experience. Ishmael uses this side-by-side comparison as a framework for a meditation that moves from anatomy into philosophy.
The Whale's Divided Vision
The chapter's most sustained passage explores the sperm whale's eyes, which are positioned far back on the sides of its massive head. Because of this placement, the whale can never see an object directly ahead or directly behind—its visual field is roughly sixty degrees on each side, leaving two enormous blind spots. Ishmael compares this to a man forced to "sideways survey objects through your ears," concluding that a whale effectively has "two backs" and "two fronts." Moreover, the cubic feet of solid head between the eyes mean each eye sends a completely separate image to the brain, as if the whale looks out through two isolated windows rather than man's paired sashes.
A Philosophical Puzzle of Consciousness
Ishmael then poses a striking epistemological question: can the whale's brain simultaneously process two entirely distinct visual fields in opposite directions? He notes that even humans, with overlapping vision, cannot attentively examine two objects at the same instant. If the whale can do what we cannot, it would be "as marvellous a thing in him, as if a man were able simultaneously to go through the demonstrations of two distinct problems in Euclid." Ishmael speculates that this divided vision may explain the famous "vacillations of movement" and "queer frights" whales display when surrounded by boats—a "helpless perplexity of volition" arising from contradictory visual information. The whale's tiny, nearly invisible ear reinforces the theme of vast beings perceiving the world through strangely small organs, and Ishmael closes the sensory discussion with an admonition: do not try to "enlarge" your mind—"Subtilize it."
Inside the Sperm Whale's Mouth and Jaw
The chapter concludes with a physical tour of the sperm whale's interior. Ishmael describes the mouth as "beautiful and chaste-looking," lined with a glistening white membrane "glossy as bridal satins." The lower jaw, compared to "the long narrow lid of an immense snuff-box," reveals rows of teeth that resemble a "terrific portcullis." Ishmael recounts how whales sometimes float motionless in the sea with their fifteen-foot jaws hanging straight down—a posture he attributes to a kind of whale hypochondria. Practically, the jaw is unhinged and hoisted aboard so that Queequeg, Daggoo, and Tashtego can extract its forty-two ivory teeth, which are fashioned into canes, umbrella-sticks, and riding-whip handles. The jaw itself is sawn into slabs and "piled away like joists for building houses."