There is a very interesting contrast in the characters of Tom Sawyer and Huckleberry Finn. The contrast is most evident precisely in their attitudes towards other people. We find in Tom a more angry, vindictive and malicious persona than what we see in Huck.
Tom is mischievous by nature and he behaves badly because he enjoys it. Huck is pretty much the follower and only causes trouble for minor reasons, such as not wanting to do one thing or another. Together, however, Huck and Tom are dynamite. One leads, the other follows, both do something. It is certainly one of the most interesting relationships in literature.
In chapter 2, we see Tom again instigating a prank against Jim. During the planning and plotting of the prank we see how Tom was sure of himself, delighted with the idea, and more than willing to bother something or somebody, namely, Jim. Contrastingly, Huck was a bit more concerned, felt unsure, and not as willing as Tom. Yet, Huck simply cannot help himself from the spell that Tom's personality seems to cast over him.
When we was ten foot off Tom whispered to me, and wanted to tie Jim to the tree for fun. But I said no; he might wake and make a disturbance, and then they'd find out I warn't in. Then Tom said he hadn't got candles enough, and he would slip in the kitchen and get some more. I didn't want him to try. I said Jim might wake up and come. But Tom wanted to resk it; so we slid in there and got three candles, and Tom laid five cents on the table for pay.
This passage is essential in understanding the huge difference in reasoning between Tom and Huckleberry. Tom jumps into action without thinking....he even PAYS to make a prank happen! Huck seems to use his brain more and is slightly more careful than Tom. Even though Huck always ends up doing as Tom asks, there is enough evidence to point that, to Huck, Jim is someone he likes. Perhaps he did not want Jim to get hurt by Tom's pranks. In all, from the two of them, Huck genuinely seems to care more for people, and for his own safety, than Tom.