In "A Defence of Poetry," Shelley suggests that emotions experienced in life are constantly changing. Which lines from "Mutability" can also be seen as a reflection of this idea?
• Streaking the darkness radiantly!-yet soon
Night closes round, and they are lost for ever
• We rest.-A dream has power to poison sleep:
We rise. One wandering thought pollutes the day
O We feel, conceive or reason, laugh or weep:
Embrace fond woe, or cast our cares away
O Man's yesterday may ne'er be like his morrow;
Nought may endure but Mutability.