The poem begins to describe things in nature that are commonly perceived as being beautiful. Then the speaker compares his mistress as being nothing like these beautiful things. It is ironic that the two extremes seem to affect the speaker in the same way. The poem seems to demean the mistress, but it actually demeans the things in nature that he describes. The speaker does not love her despite her differences; he loves her because of them.
The speaker's attitude toward his mistress in the beginning is negative. It sounds like he is insulting her. The tone of the poem shifts when the speaker says, "I love to hear her speak, yet well I know / That music hath a far more pleasing sound," (9). Here the speaker indirectly pays his mistress a compliment. In the last two lines of the poem the speaker states that his love for her is rare. The speaker is not negative towards his mistress. He is disapproving of the commonly held ideas of beauty. The speaker shows that he loves the mistress' odd attributes by the shift of tone in the sonnet.
Shakespeare's sonnet leaves the reader pondering, "What is beauty?" It can be assumed by the reader that the mistress is ugly, but the speaker never says that she is ugly. He only shows that she is different. The speaker deems his mistress worthy of comparison with these great things in nature. The comparison alone does not say how the reader feels about the things he compares his mistress to. In the end the speaker expresses his love for his mistress. He does not say that he