In Shakespeare's Sonnet 18, the speaker asks permission or suggests that he will compare his beloved to a summer's day.
Shall I compare thee to a summer's day?
Thou art more lovely and more temperate:
Actually, the beloved is more lovely and more constant than a summer day. Still, the writer captures the beauty of his beloved in a comparison of her beauty and a warm day in summer. Of course, he mentions that a summer day is often too short, but he claims that his beloved's youth shall not fade.
Although summer can be too hot or too short, in this poem, the beloved is perfect. To compare her to a summer's day gives an idea of her beauty, but in reality, she is far more beautiful than a summer day. For his beloved will not fade or lose her beauty, but a summer day will end. Not even death can claim his beloved. She becomes immortal in the words of this poem.
Truly, his beloved has become immortal. That is the difference in a summer day and his beloved. A summer day will end, but his beloved will forever live on in the sweet verse of this poem:
But thy eternal summer shall not fade, Nor lose possession of that fair thou ow'st, Nor shall death brag thou wander'st in his shade, When in eternal lines to time thou grow'st.
So long as men can breathe or eyes can see,
So long lives this, and this gives life to thee.
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