Fear is a good theme of the book because bigger runs into a lot of fear. First when Bigger kills the daltons daughter and he what he is going to do about it. He never has done something like this befor but he knows if he gets cought he will be killed by the white people. This is why he is so scared about it. Its like the first time you stold something, where you affraid. Also Bigger thinks they will think he rapped her. So there is more fear deep down inside he can not let out.
Even though he did not really rape her he is black and they will not beleave him. So he thinks he will need to cover it up just so he does not get in trubble. So he throws her body in the firie hot fernice to burn and cover up the evedence. (Not the best idea but what he thought in his panic) deep down inside he knows he wrong but sence of his manley figure he can not think he is in the wrong with things. So he yells at bessie tring to get himself to beleave he is not wrong. "Well i aint wrong now!!!! just like i have never been." Now is when the chriminal inside of him kicks in and he desides that he did it so he should make some money off of it. He fears veing cought all though he still sends the ransom note.
Bigger also fears his girl bessie knows too much about the situation so he can not leave her behind. so his chriminal mind desides he IS GOING TO KILL HER. Not the best idea but he has so much fear deep down inside of him that he thinks this is the best way to cover everything up. I do not know why he does this but i beleave that it is becaus he is so deathly scared for his life. So Bigger trys to over power people that have less strangth. (girls)"Id never thought it would be like this, me running from the cops with you. OH WHAT HAVE I DONE!!!" Bessie said this in her fear of what she has got herself into. Bessie beleaves she has chosen the wrong path now. This guy is a CREEPER that has a lot of energy and fear inside that he cant find a way to let out like a normal person. So Bigger desides to just kill to make himself think he is in the right.