Shakespeare's Sonnet 4 on Masturbation
The poet wants the young man to seed a woman who ideally will bear him a lad, thus sustaining his manly beauty in a son. SONNET 4 Unthrifty loveliness, why dost thou spend Upon thyself thy beauty's legacy? Nature's bequest gives nothing but doth lend, And being frank, she lends to those are free. Then, beauteous niggard, why dost thou abuse The bounteous largess given thee to give? Profitless usurer, why dost thou use So great a sum of sums, yet canst not live? For having traffic with thyself alone, Thou of thyself thy sweet self dost deceive. Then how, when Nature calls thee to be gone, What acceptable audit canst thou leave? Thy unused beauty must be tomb'd with thee, Which, used, lives th' executor to be.
