Why does lovely music sadden this young man? Shakespeare blames his bachelorhood
Sonnet 8 opens with a puzzle: a young man who is himself like music listens to music and grows gloomy. Shakespeare's answer is sly. Harmony, he says, is a family portrait in sound, strings married to strings, and its chords scold anyone who insists on staying single.
The first quatrain is a run of questions. Sweet things do not fight sweet things, and joy enjoys joy, so why does the listener love something he takes in without pleasure, or welcome what annoys him? The contradictions set up a diagnosis rather than a complaint: the trouble lies with the listener, not the tune.
Next the poem turns harmony into a lecture. Well-tuned notes joined in concord, the speaker says, only offend this ear because they gently rebuke a man who blurs, by living alone, the separate parts he ought to be playing. The musical vocabulary doubles as marital vocabulary: unions, married sounds, parts to bear. A chord becomes an argument for a wedding.
The third quatrain gives the most vivid picture. One string, called a sweet husband to the next, sets it vibrating in sympathy, and together they resemble a father, a child and a happy mother singing a single agreeable note. The couplet lets that wordless music speak its moral aloud, and the line lands like a verdict: "Thou single wilt prove none." One note alone, in the logic of the poem, amounts to nothing; only in combination, and by implication in children, does a voice persist.
A poet so keen to see others wed had taken the step young himself. Shakespeare's own marriage came early and in apparent haste: at 18 he wed Anne Hathaway, then 26, after the Diocese of Worcester issued a licence on 27 November 1582, with the banns read only once. Their daughter Susanna was baptised in May 1583, and twins Hamnet and Judith followed in February 1585. Hamnet died aged 11 in 1596.
Source: Sonnet 8: Music to hear, why hear'st thou music sadly?