Symbolism, Imagery, Allegory
There are plenty of scenes in this book where you have a group of men sitting around a fire at night. And sooner or later, they're bound to get a little philosophical. As the narrator mentions at one point:
The flames sawed in the wind and the embers paled and deepened and paled and deepened like the bloodbeat of some living thing eviscerate upon the ground before them and they watched the fire which does contain within it something of men themselves inasmuch as they are less without it and are divided from their origins and are exiles. (17.13)
McCarthy connects fire to the most basic existence of humanity in scenes like these, and for a brief second it seems as if these men have found a sense of peace. But it only lasts until the killing starts again, which seems to happen on almost every other page.