Why was Wright so angry at Uncle Tom?

Since Wright is getting older and older, at this age, it seems that he is now able to understand more of what he deserves and what he doesnt deserve, justice vs. injustice. In the first chapter of black boy, Wright is hiding under the house terrified of getting a beating because he know he deserves it - he knows that what he did results in a punishment. But as he grows up and learns to defend himself and becomes more aware of the outside world, he realizes that certain instances are not his fault and he must defend himself. in chapter 6, as Wright is scouting for jobs and going into white people's homes, he is introduced into another world. the first home the white lady told him basically that he will never amount to anything and will never become a writer. she fed him moldy mollasses. in the second home, he was called such ill names and treated with such little respect, while the white spoiled family ate their bacon and eggs. immediately after those two encounters wright left those homes, knowing that he will not be treated that way. he does not deserve it. and so when this situation with uncle tom comes up, and wright was only just being himself, answering to toms question as he always would - he knows that he did not say or do anything that deserves an awful whipping. uncle tom does not live with him, he does not know wright, he is only angry. and instead of taking the whipping, wright will not stand for something he doesnt deserve. through his anger out of uncle tom's injustice, he is willing to fight.