A literal example of Douglass's discussing the power of literacy occurs when he plans his first attempt at escaping to the North. He has taught several slaves on the plantation how to read, and he himself has improved his own skills over the course of the years. He is able to forge documents that allow him and others the opportunity to escape. Of course, this plan is ruined by an information leak and the men are caught; however, once Douglass realizes that he is being chased, he knows that he must destroy the forged passes. The passes are so powerful that as evidence, they could lead to harsher punishment for the men.
I would think that locating quotes when Mrs. Auld starts to teach Douglass how to read might be where the idea of the power of literacy could be evident. The fundamental argument that Douglass makes is that the introduction of literacy can help prove the anti- American spirit of slavery. As one learns about the theoretical promises and possibilities in the creation of America through reading its founding documents, one gains a better insight that can logically disprove the justifications behind slavery. Education becomes the tool by which Douglass believes that the end of slavery can be brought about and through its denial, he understands that this is one more attempt to continue what is morally and politically wrong.