One of the forms of analysis and criticism that is best used with many works is the analysis of archetypal images. Many words and objects are images that have much deeper meanings and values than you, as a reader, take at face value. Many of the words and sentences in Dylan Thomas’ “Do Not Go Gentle Into That Good Night” give away the poems underlying theme of darkness and death.
One of the archetypal images Thomas uses is that of the wise old man. “Though wise men at their end know dark is right, because their words forked no lighting they do not go gentle into that good night.”