why do he pigs teach them selves to read and write?

The pigs take on the task of organizing and teaching the other animals because they are “generally recognized as being the cleverest of the animals” (35). The pigs become the organizers very quickly. It is important to note two things about their rise to power. First, the pigs have not always been in charge of the other animals, though later in the book when the pigs are so thoroughly demonized, Orwell makes it hard for the animals—and the reader—to remember that. But they are superior by nature—or at least by tradition—when it comes to intelligence. Second, the pigs’ intentions are not necessarily bad at first. They take on the task of organization because of their reputed superiority rather than a desire to take control for themselves. Just as Boxer is best suited for hard manual labor, the pigs take their place for organizational work in the animals’ division of labor.