What might the story of the mule reveal about Joe?
The symbolic meaning of a mule as a creature who is worked and used and exploited is certainly a common one. In Chapter 6 of Their Eyes Were Watching God, Janie enjoys being on the porch, listening to the rich tales that the men spin about Matt Bonner's overworked and underfed mule. And, all the while the men tease Matt constantly about feeding his mule, he insists that he takes care of the poor beast. Finally, Joe buys the mule from Bonner because he wants the suffering animal to spend the rest of his life in comfort. His humane act inspires Janie to praise him,
"Freein' dat mule makes uh mighty big man outa you. Something like George Washington or Abraham Lincoln...You have tuh have power tuh free things and dat makes you like uh king uh something."
Thus, Joe gains respect from her and others. In addition, he has asserted his power as he is able to purchase the animal for no other reason but to establish the animal's comfort. Further, he has also put an end to the tales created by the men, and even gets the last word in at the "draggin' out" to which he forbids Janie to attend as it is "common."
Once again, Joe's power restricts Janie. But, having experienced the convivial spirit of the men on the porch as they banter about the mule, Janie realizes that there is much to life that she desires. While Joe is not a mean or cruel person, his chauvanistic motives quell the spirit of Janie. Like the poor mule who has been exploited in both life and death, Janie's spirit, too, has been hindered and her person exploited as Joe keeps her in the role of dutiful wife.
The story of the mule is included in the text because it helps demonstrate the language and culture of Eatonville. The residents often use the mule as a way to poke fun at not just the mule's owner, Matt Bonner, but the other residents as well. The colorful hyperbole they use in teasing each other is a source of entertainment, but it isolates Janie because Joe never allows her to take part. One day, when Joe overhears Janie talking about how inhumane it is to let the mule suffer, he buys the mule so that it can rest. This act demonstrates the care he has for Janie, but it also demonstrates how he loves to appear benevolent to the townspeople. Once the townspeople praise him for having mercy on the mule, he never credits Janie by telling them it was her idea.
How the mule reflects Janie is a trickier issue. Janie's best friend Phoeby, often comments on how nice it must be for Janie not to have to work for a living (even though Joe makes Janie help out in the store). It seems that Joe realized that others would admire him for having such a beautiful wife. Along the same lines, others admired him for taking pity on the mule as well. Both Janie and the mule have lives of leisure because neither of them are expected to work. The only difference is that Janie wouldn't mind working alongside the others, because then she wouldn't feel so isolated and lonely.