You've got a bigger problem then a black supervisor who seems to be progressively loosing his marbles. Keep your head down, treat the guy with courtesy and focus on being proficient in your job. Collect your pay, pay off your debts, build up your savings. Then focus yourself on learning skills that can net you a bigger paycheck, ideally in a field that blacks likely don't pursue entry. Whatever field you're in, if a black guy is there, then it's safe to assume some females maybe as well. If this is the case the job, or field is probably a few years away from obsolescence. Make your gains and get the hell out before the layoffs begin.