Two prevalent universal elements that feature in many of Shakespeare's sonnets are the themes of aging and love.
Shakespeare wrote many sonnets that featured the theme of aging, addressing his own personal fears concerning the topic and his view of his own role in the world around him. Sonnets 30, 60, and 73 are a prime examples of his fears related to aging. In "Sonnet 73," Shakespeare compares his old age to the passing of the fall season, demonstrating his keen perception of nature as he compares himself to "the twilight of such day as after sunset faded in the west."
"Sonnet 116" addresses the steadfastness of love, comparing true love to "an ever-fixed mark that looks on tempests and is not shaken." In some of his sonnets, Shakespeare addresses different aspects of his love, whether it is the appeal or quality of his or his lover's commitment to the relationship. In "Sonnet 18," Shakespeare compares his beloved to "a summer's day" who is "more lovely and more temperate."