quote a scene segment that involves Macbeth.

“Out, out, brief candle! Life's but a walking shadow, a poor player that struts and frets his hour upon the stage and is heard no more. It is a tale told by an idiot, full of sound and fury, signifying nothing.” Act 5

Macbeth is pretty depressed at this point. He finds life pointless. He feels that life is brief and lacking any substance. People don't learn from the past, merely walking stupidly to their end.