Why is the ability to read and write a statement about freedom?

Frederick Douglass was a slave and his freedom was suppressed by not being able to read and write. Frederick was not able to read because there was not enough time. Another reason is if the black folk were able to read it would make them closer to the intelligence of the white person. The reason why this is so big is because being able to read and write is a basic skill for most people to have. The whites just liked to take away basic and common skills. What this did for them was to prove their superiority even though we all are equal. Back then, when slavery was a thing making a statement was the biggest thing you can do. A statement can put a drive in the hearts and souls of a group of people or distinguish fear in the eyes of the receiver.