Jim first meets the ship's sea-cook Long John Silver in Chapter 7, encountering him by chance in Bristol. When Jim notices that one of Silver's leg is cut off at the hip, he wonders if Silver is the dangerous pirate Billy Bones warned him about. But Silver is "intelligent and smiling" and seems much different from the other pirates Jim has encountered so far:
I had seen the captain, and Black Dog, and the blind man Pew, and I thought I knew what a buccaneer was like—a very different creature, according to me, from this clean and pleasant-tempered landlord.
The "Captain" Billy Bones, Black Dog, and Pew are all pirates Jim encounters at the Admiral Benlow. Early in the novel, Jim describes Bones as "soiled" with "hands ragged and scarred" and "black, broken nails." When Jim first encounters Black Dog, he describes the pirate as a "pale, tallowy creature, wanting two fingers of the left hand." Upon meeting Pew, a third pirate, Jim declares that "I never saw in my life a more dreadful looking figure." In comparison to these intimidating figures, Silver certainly appears more welcoming. Jim decides "one look at [Long John Silver]" is enough to change his mind, and he mistakenly takes Silver's sunny exterior at face value.
However, Jim and the reader soon learn that Silver will go to great lengths to ensure his own survival, even if that means betraying Jim or the other characters. In Chapter 14, Jim finds out Silver is spearheading a campaign to commit mutiny. This unexpected turn of events is an example of situational irony. Silver's duplicitous nature initially disillusions Jim. Later on, however, Jim comes to respect Silver's craftiness and joins forces with Silver in order to survive. In presenting a tension between Silver's outward appearance and true nature, Stevenson warns readers that appearances often hide what lies beneath. By the end of the novel, the reader is able to have a more nuanced perspective on Long John Silver. All in all, Treasure Island offers a message to readers that human nature and life isn't black and white. Growing up isn't simply a matter of knowing what's "right" or "wrong." Rather, the novel implies that becoming independent and responsible for oneself is what really matters.