express the idea that everything beautiful and fair eventually fades or diminishes, either due to chance or the natural progression of time.
The purpose of these lines from "Sonnet 18" by William Shakespeare is to express the idea that everything beautiful or fair in this world will eventually decline or fade away. This theme of the transitory nature of beauty is common in Shakespeare's sonnets. In these specific lines, the poet suggests that fair things lose their beauty due to either chance or the natural course of life, and that they are not always preserved in their pristine state. The concept of decay and impermanence is poetically presented in order to highlight the speaker's central argument in the sonnet, which is that their beloved's beauty will be eternalized through the power of poetry.
