Hall states, "The primary task of the psychoanalyst is to discover the precise impact on the psyche of environmental factors..." (106). From the very beginning of the song, the singer is observing what is going on in his outside environnment: "I see the kids in the street/With not enough to eat/Who am I, to be blind?/Pretending not to see/their needs." The effect of this environment on the singer is evident in the chorus. He has been filled with a sense of guilt and shame, and is now motivated to better his outside environnment by first improving himself: "If you wanna make the world a better place/take a look at yourself, and/then make a change."
Hall also mentions how texts may have a psychological impact on readers, and how "narrative forms meet readers' deep-seated psychological needs for control and self-gratification" (109). I believe it is safe to say that most readers/listeners desire peace and harmony, and in that vein, the text certainly speaks to them. This desire for world peace in "Man In The Mirror" highlights what Hall says about mass-psychological forces, and their relationship with texts (on page 110).