Name the white parts of a black person: His palms, his foot soles, his eyes, teeth, and his owner
What response were you hoping to achieve with this statement?
I want people to understand that black people were slaves owned by white people, so we have more rights than them
You're right that black people were owned as slaves in history, but this is only because white people invaded their homeland and took them at gunpoint.  Nothing about this shameful history suggests that certain people have more rights than others in today's society, and making jokes about slavery continuing is in pretty bad taste.