What does Douglass say is his first view into the violence of slavery? Why was this knowledge new to him?

Slave children always followed the condition of their mother, a fact Douglass noted was no doubt due to slaveowners' pernicious lustful designs upon slave women. Children born from slave mothers and white fathers – mulattos – experienced far more difficulties than did other children. They must always fear the wrath of the slaveowner's wife; their presence was a constant reminder of her husband's infidelity. The slaveowner himself must watch his white sons abuse their black brothers. It is actually best if he sells these children to another slaveholder.