At one point in the John Steinbeck's novella, Kino tells his brother Juan Tomas, "The pearl has become my soul." What he means by this observation is that the pearl has taken over his existence; all that Kino thinks about, all that he lives for, is the pearl in the hopes of changing the social and economic condition of his family's life.
However, with the pearl having become his soul, Kino has lost his identity and separated himself from his family unit by stepping outside to fight intruders, and by separating himself from the community who could have shared in his wealth as well as protected him. Then, after the assaults upon him and his boat, Kino becomes
an animal, for hiding, for attacking, and he lived only to preserve himself and his family.
But, without the aid of others of his own kind, Kino's stubbornness foils his chances for wealth, and, instead, tragedy strikes him as his obstinance and the oppressors reduce him to less than a man. Having upset the natural order of his group, Kino must return the pearl, that Juana perceives as evil, to the ocean so that they may readapt to their community.