How do the themes of guilt and responsibility aries in relation to Miigwan in the chapter The Long stumble?

Miig tells Frenchie that he didn't want to live when Isaac couldn't escape. He kept going because he made a promise to himself to go back and save Isaac. Miig tells Frenchie that while they will inevitably lose people, it's still important that he keep working toward improving the world for future people.just as as Miig did by working with Dad in order to return to Isaac.