What does percy learn about chiron in ch 6?

What do you think is the greatest invention that you use today? explain in 4 sentences

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?

The room was gaudy with its leather couch and purple walls