Why did Jim run away?

Jim ran away after he heard Miss Watson talking about selling him for 800 dollars.  Jim didn't wait to see if she actually was going to sell him, but he ran away so he wouldn't have to go to New Orleans.  Jim was afraid that he would have to leave everyone he knew and cared about behind. Jim ran to an island where he eventually found Huck.  Jim seemed to be afraid but not regretful of running away.  Jim has to worry about the rough punishment that is instilled on run away sla