A Presbyterian from Tisbury in Martha’s Vineyard, Flask serves as the third mate aboard the Pequod. The eager and belligerent approach that he takes to killing whales sets him apart from Stubb’s easy-going nature, and his often shallow thinking contrasts with Starbuck’s analytical tendencies. While these distinctions are significant in terms of the ways in which they shape the dynamics among the crew members, one of the most important aspects of Flask’s character lies in the similarities he has to Captain Ahab. Both men have an aggressive attitude toward whale hunting and, given Flask’s nickname of “King-Post,” a sense of self-importance. The key difference between Flask and Ahab, however, is the depth with which they interpret the world around them. Flask’s straightforward and sometimes naïve attitude makes Ahab’s internal struggle appear even deeper, thus reinforcing the notion that the captain’s hunt for Moby Dick is about much more than simply killing a whale. 

Melville establishes a link between Flask and Captain Ahab early in the novel in order to highlight the role that interpretation plays in determining their fates during the remainder of the voyage. In Chapter 27, Ishamel describes Flask’s impulse to “destroy [whales] whenever encountered,” a mindset which ultimately has eerie similarities to Ahab’s singular mission of killing Moby Dick. The apparent sense of enjoyment Flask feels while hunting whales also allows him to stay committed to a particular voyage for an extended period of time and, along with his short stature, earns him the nickname “King-Post.” While this term comes from a central piece of a ship’s construction, the sense of authority that the term “king” evokes reflects his ambition and connects him to Ahab’s kingly rule over the Pequod

At the same time, however, Flask’s shallow understanding of his environment pales in comparison to Ahab’s obsessive and overly analytical point of view. Ahab may see Moby Dick as an embodiment of evil, but Flask merely sees whales as “a species of magnified mouse.” Comparing Flask’s interpretation of whales to the insignificance of a mouse, especially after the Extracts chapter highlights the massive cultural impact of whales, emphasizes his inability to see the larger meanings and implications of the world around him. A similar effect occurs in Chapter 99 when Flask admits to viewing the gold doubloon as nothing more than money, failing to find the kind of symbolism in it that many of the other crew members do. Alternatively, Ahab imposes so much meaning onto Moby Dick that it drives him to lead an entire ship to its doom. Using Flask as a point of comparison for Ahab allows Melville to suggest that the Pequod’s voyage is not just about a desire to hunt for the White Whale, but rather a need to pursue the meaning that one man’s worldview has imposed upon it.