A great section of this text to examine is Chapter VI, when the narrator describes his initial experiene of being taught how to read by Mrs. Auld, his new mistress. This continues until Mr. Auld discovers what his wife is up to, when he puts a stop to the classes. What is particularly worthy of attention are his reasons why slaves should not be taught how to read:
A nigger should know nothing but to serve his master--to do as he is told to do. Learning would spoile the best nigger in the world. Now... if you teach that nigger how to read, there would be no stopping him. It would forever unfit him to be a slave. He would at once become unmanageable, and of no value to his master.
Overhearing this conversation triggers a massive epiphany in Douglass, as he finally understands how it is that white men have been able to overpower and dominate black men like himself. He connects education to freedom, and at once resolves to embark on a journey to become as educated as possible as he recognises that becoming educated will equip him to challenge his position as slave and "ruin" him by preventing him from playing the role of the slave any further. Ironically, Douglass recognises that Mr. Auld, far from halting his educational advances, actually spurred him on, as his words encouraged him to pursue education zealously as part of his journey towards freedom.
In Chapter Six, Douglass is staying with the Aulds. Sophia Auld, initially a kind woman, starts to teach him how to read. Mr. Auld stops the lessons as soon as he realizes what is going on. He says that teaching a slave to read would spoil the slave (he doesn't use those exact words...).
Douglass realizes that since Mr. Auld doesn't want him to learn to read, he determines to do so. He finds school copy-books and secretly traces the words inside it. He finds poor white boys and bribes them with bread in order to teach him how to read. He finds a copy of The Columbian Orator and begins to read it. The book contains a famous speech between a master and a slave, in which the master lists the reasons that slavery is justified and the slave refutes each and every one. The speech moves Douglass emotionally.
After he has learned to read, Douglass realizes that the slaveholders do not teach their slaves to read because it is only then that the slave can realize just how unfair their lot is. He starts reading abolitionist newspapers. Douglass experiences an existential crisis because he realizes that while learning to read has set his mind free, he is still a slave, and that he wishes that he were uneducated again, because he believes his plight is worse off than an uneducated slave.