Narrative of the Life of Frederick Douglass
How we cite our quotes:
After apologizing for his ignorance, and reminding the audience that slavery was a poor school for the human intellect and heart, he proceeded to narrate some of the facts in his own history as a slave, and in the course of his speech gave utterance to many noble thoughts and thrilling reflections. (Preface.4)
Partly, Douglass is just being humble. He's giving a speech in front of a big audience, and he's never had much practice or training for that kind of thing. So he wants to remind his listeners not to judge him too harshly. At the same time, though, when Douglass calls slavery a "poor school for the human intellect and heart," he's reminding people that while slaves might often not seem to be as smart or as well-spoken as white people, this isn't their fault. Instead, it's the fault of the masters who enslaved them. After all, while Southerners would often claim that black people should be slaves because they were born inferior, Douglass thinks this is backwards: slaves aren't born inferior, but rather it's slavery that makes them inferior.
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.
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.