The poet now argues that the young man needs to have a child in order to maintain a balance in nature, for as the youth grows old and wanes, his child's "fresh blood" will act as a balance to his own old age. The young man is irresponsible not to have a child, for if others acted as he does, within one generation the entire human population would die out. The young man's actions are not onlyirresponsible; they are also unnatural. Nature, according to the poet, intended people who are able to have children to have them. Those people who refuse to have children are unnatural and upset nature's balance.
Encouraging the youth to reproduce, the poet draws an analogy between procreation and writing poetry. The images of Sonnet 11 suggest that procreation and posterity reflect art and craftsmanship: "She carved thee for her seal, and meant thereby / Thou shouldst print more, not let that copy die." The young man, should he die childless, effectively kills any lasting image of himself through his children.