Explanatory
Though Native Son is peppered heavily with dialogue, it is also interspersed with long passages that illuminate Bigger’s motivation:
There was silence. The car sped through the Black Belt, past tall buildings holding black life. Bigger knew that they were thinking of his life and the life of his people. Suddenly he wanted to seize some heavy object in his hand and grip it with all the strength of his body and in some strange way rise up and stand in naked space above the speeding car and with one final blow blot it out—with himself and then in it. His heart was beating fast and he struggled to control his breath. This thing was getting the better of him; he felt that he should not give way to his feelings like this. But he could not help it. Why didn’t they leave him alone? What had he done to them? What good could they get out of sitting here making him feel so miserable? (1.1066)
Even though the point of view of the book is Bigger’s, we are treated to explanations of his behavior that he himself doesn’t vocalize... and emotions that are so immense and incomprehensible that they're referred to as "the thing(s)."