When Bastion was born, with only 1 arm, his parents abandoned him to a local orphanage. The injustices in his early life have fuelled him with a desire to make everything in the universe "fair". There was nobody there to help him as a child so he is now instilled with a desire to help everyone around him. He still holds a fair bit of resentment to the parents who abandoned him as a baby.

Hosnian

60
Morality
Justice: The character strives for just and deliberate actions in his life and in his interactions with others. He attempts to make the objectively right choice every time, knowing that justice is more likely to guarantee positive outcomes than sympathy or other emotional displays.
Cruelty: All too often, the cruel use justice to excuse their actions. If one stops himself from tempering justice with empathy and understanding, he can inflict great harm on others and feel justified doing it. Eventually he can grow to revel in the suffering of others, even as he deludes himself into thinking he makes the "just" choice.