The symbols Shakespeare uses in this poem serve to enhance the imagery he creates in describing everything his lady is not. For example, he uses snow as a symbolic standard of a pure, pristine complexion, and his love, whose skin tone is "dun", does not measure up. In a similar manner, Shakespeare uses the sun, roses, and music as symbolic ideals of the radiant eyes, rosy cheeks, and melodious voice that he would expect to find in a classic beauty, and again, his lady is lacking in these areas. Shakespeare uses these symbols to create an image of the traditionally accepted measures of comeliness. In a tone that is playful, tongue-in-cheek, and self-effacing in a way, he makes a comment on the importance of these measures, or perhaps on the foolishness of his own judgement. Although his love is not a beauty, he loves her still.