being black because your skin color reflects what you really are in society, being black means that you can not have hands in your pockets, no playing music, no sudden movements, no driving your car, no walking at night, no walking at day, no turning on to the street, no entering this building, no standing your ground, no standing here, no standing there, no talking black, no playing with toy guns and no living while your black.
What both Luther and Rankine wanna get across is the idea of the self fulfilling prophecy. If you treat someone as worthless, eventually they will start to believe it.