Once the last trace of emotion has been eradicated, nothing remains of thought but absolute tautology.
You have to start with slavery because those abuses have never been eradicated. You know, people are not living in slums because they voted to. You know, their children are not in jail because they wanted them to. You know, these are the results of a people who have been oppressed and suffer national oppression, you know.
Progress is always relative: to the oppressed, it can only be viewed as an all or nothing deal – if oppression continues, even in a modified form, then the system must still be attacked until that injustice is eradicated.