Quote 13
I look upon my departure from Colonel Lloyd's plantation as one of the most interesting events of my life. It is possible, and even quite probable, that but for the mere circumstance of being removed from that plantation to Baltimore, I should have to-day, instead of being here seated by my own table, in the enjoyment of freedom and the happiness of home, writing this Narrative, been confined in the galling chains of slavery. (5.11)
There are many reasons Douglass might still be a slave if he had never left Colonel Lloyd's plantation, but his comparison of the chains and the writing table shows one of the most important: it was only after he went to Baltimore that it became possible for him to expand his horizons and learn to read and write.
Quote 14
Whilst I was saddened by the thought of losing the aid of my kind mistress, I was gladdened by the invaluable instruction which, by the merest accident, I had gained from my master. Though conscious of the difficulty of learning without a teacher, I set out with high hope, and a fixed purpose, at whatever cost of trouble, to learn how to read. The very decided manner with which he spoke, and strove to impress his wife with the evil consequences of giving me instruction, served to convince me that he was deeply sensible of the truths he was uttering. It gave me the best assurance that I might rely with the utmost confidence on the results which, he said, would flow from teaching me to read. (6.3)
When Mr. Auld prevents Mrs. Auld from teaching Douglass how to read, he's disappointed that his education has been interrupted. But even though it becomes more difficult to learn to read after that, Douglass learns something even more important from the experience: the power of education. The fact that Mr. Auld doesn't want him to read shows him that there's something valuable there, and makes him want to learn to read even more.
Quote 15
The first step in her downward course was in her ceasing to instruct me. She now commenced to practise her husband's precepts. She finally became even more violent in her opposition than her husband himself. She was not satisfied with simply doing as well as he had commanded; she seemed anxious to do better. Nothing seemed to make her angrier than to see me with a newspaper. She seemed to think that here lay the danger. I have had her rush at me with a face made all up of fury, and snatch from me a newspaper, in a manner that fully revealed her apprehension. She was an apt woman; and a little experience soon demonstrated, to her satisfaction, that education and slavery were incompatible with each other. (7.2)
When Mrs. Auld stops teaching Douglass, he learns a valuable lesson: education and slavery are incompatible. For Mrs. Auld, the more she learns about slavery, the more fearful and angry she becomes.