What is the essence of Northup’s description of Southern slavery?

Not only was slavery problematic for the African Americans caught in its grasp, but, Northup writes, it also corrupted any and all in its path — including white people. It made white people who were otherwise kind or moral into tyrants. It raised children in an environment where brutal treatment of slaves was considered the norm. Violence, sexual abuse, and cruelty were de rigeuer on many plantations; owning slaves and doing what one wanted with them was seen as right and normal. Even the generous and Christian Mr. Ford was raised in this milieu. Mrs. Epps was otherwise a wonderful woman, but she was corrupted by having power over Patsey, the slave with whom her husband had relations. Overall, slavery was bad for the economy and environment of the South, bad for free labor, bad for slaves, and bad for the white people who participated in it.