What does gene do when Quackenbush accuses him of being maimed? what motivates gene to respond this way? in what sense might gene be maimed?

This occurs when Gene is securing his role as the
Assistant Crew Manager. This is not an honorable, but a mocking position for a senior.
Gene starts a fight with him. The two end up wrestling through the fight falling into
the river.

I think Gene's purpose for responding this way
is that he has an over-sensitivity to the word maimed because of it's significance about
what he knows he's done to Finny. To have crippled someone else and that someone not
knowing is maiming Gene from the inside out.

Gene's spirit
has been crippled at the loss of Finny's ability to be himself. Gene is crippled by
guilt. Gene is crippled by untruth.