How would the other prisoners view a peer who returns from outside the cave?

Answer- The escapted prisoner represents the Philosopher, who seeks knowledge outside of the cave and outside of the senses. The other prisoners reaction to the escapee returning represents that people are scared of knowing philosophical truths and do not trust philosophers.
Hope this helps:)

just as

Explanation:

"So Eden sank to grief", The "so" at the beginning of the line means "just as," which means that in line, the speaker is comparing mankind's fall from the Garden of Eden to the change from gold to green he described in the first half of the poem.