No one likes it when someone copies them, or wears the same outfit, or has the same shoes. We all want to have our own identity, our own sense of self, right? Okay, so imagine, then, that you are an exact genetic copy of someone else. How in the world are you supposed to be original, when you are literally identical to someone else, right down to your very genes? It's a problem that Matt deals with all throughout The House of the Scorpion, and his identity issues are further complicated by the fact that he's cloned from a Very Bad Man. That's right, Matt's the exact genetic copy of El Patrón, a ruthless dictator and drug lord. As he grows into manhood, Matt has to fight not to follow in El Patrón's footsteps. He struggles to be his own person and make his own decisions. And he's not the only one. Everyone in Opium is under El Patrón's control, and it's hard to be yourself when you have a man like that watching over you. In the end, Matt discovers that he can create his own identity by making choices – decisions that are his and his alone.
For Matt, creating an identity that has nothing to do with El Patrón is a very important task.
Matt becomes a nice version of El Patrón at the end of the novel, which is how Matt remains his own person while acknowledging his connection to the former dictator.