What were people doing to get bread on the train?

Messalla frowns at the wide circular cover, for a moment returning to his own fussy world.

In what ways do “the lamb” and “the tyger” represent opposite sides of human existence? a. “the lamb” urges passive control, while “the tyger” glorifies man’s dominance over nature. b. “the lamb” urges meek acceptance, while “the tyger” glorifies nature and power. c. “the lamb” urges childlike faith, while “the tyger” glorifies man’s experience.

London includes a quote about john thornton as he is observing hal attempt to motivate the exhausted dogs "it was idle, he knew, to get between a fool and his folly". if the word "idle" is defined as "of no real worth, importance, or significance", what does this statement mean with regard to hal? who is the fool? what is hal's folly? why would john thornton think it of no real worth or useless to intervene?