What does tom discover about Casey? How does Tom reacts to Casey's attack?

http://www.gradesaver.com/the-grapes-of-wrath/q-and-a/what-does-tom-discover-about-casey-how-does-tom-reacts-to-caseys-attack-75879

Because of the attack on Caset, Tom begins to question his own beliefs. He wants to carry through with the things that Casey has begun, and to help organize a revolt against the well to do planters. The attack on Casey served as an inspriration for Tom; it gave him purpoae and new understanding.