On a symbolic level, the scar is important for a couple of reasons. After the fight and the surgery, Amir's scar resembles Hassan's hair lip before his surgery. In this light, it moves Amir closer to Hassan on the road to forgiveness, almost as if he is physically resembling the form he wishes to embrace. It becomes important that Amir move as close to Hassan as possible. Since he is seeking a way "to become good again," to move closer to Hassan, who is now dead, is vitally important. The scar is one such move. Another way is how the scar was obtained. Amir was taking action against Assef's cruelty, something he failed to do as a child. It is not lost that Amir failed to take action with Hassan, but is not missing the chance to take action for Hassan's son. When Amir laughs, it is a moment of clarity present, as he feels peace, while being beaten to a pulp. It for this reason that that scar is critical on Amir's path to forgiveness and "to become good again."