Out, out, brief candle! Life's but a walking shadow, a poor player / that struts and frets his hour upon the stage And then is heard no more. It is a tale told by an idiot, full of sound and fury signifying nothing.
change in tone expresses he has finally awaken from his stupor. The nouns candle, shadow, player, and tale connate imitation and emptiness. Semantic field show how people focus on the wrong things in life. He was so focused on ambition he missed what really mattered.