LitCharts assigns a color and icon to each theme in Moby-Dick, which you can use to track the themes throughout the work.
Limits of Knowledge
Fate and Free Will
Nature and Man
Race, Fellowship, and Enslavement
Madness
Religion
Summary
Analysis
Ishmael quickly outlines the fact that, in many cultures, one is hard-pressed to find an accurate depiction of a whale, whether in painting, sculpture, or drawing. Ishmael states that Hindu, European, and even some early American accounts of whales manage to distort their size and shape, and he attributes these inaccuracies to the fact that a great many have never seen a whale alive in the water, and that most drawings come from reconstructions, or imagined versions, of whales derived from skeletons on display in museums. Ishmael wonders whether anyone might be expected to describe and depict a whale properly, if one hasn’t seen an actual whale.
Now the novel turns to a series of descriptions—scientific, biological, and artistic—concerning the whale. Ishmael does this for several reasons. First, he “holds up” the progress of the events of the novel, thus building up the suspense for the big chase at its close. Second, he fills in the background of whale-science up till this point in human history, as a way of showing just how central the whale is to nineteenth-century culture. Third, through his descriptions of that whale science he continues to build up the sense of the ultimate unknowability of whales.