“ The young dismissed to wander earth or air, There stops the instinct, and there ends the care; The link dissolves, each seeks a fresh embrace, Another love succeeds, another race. A longer care man's helpless kind demands; That longer care contracts more lasting bands: Reflection, reason, still the ties improve, At once extend the interest and the love; With choice we fix, with sympathy we burn ”
 Alexander Pope, An Essay on Man (1734). copy citation

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“Not man alone, but all that roam the wood, Or wing the sky, or roll along the flood, Each loves itself, but not itself alone, Each sex desires alike, till two are one. Nor ends the pleasure with the fierce embrace; They love themselves, a third time, in their race. Thus beast and bird their common charge attend, The mothers nurse it, and the sires defend; The young dismissed to wander earth or air, There stops the instinct, and there ends the care; The link dissolves, each seeks a fresh embrace, Another love succeeds, another race. A longer care man's helpless kind demands; That longer care contracts more lasting bands: Reflection, reason, still the ties improve, At once extend the interest and the love; With choice we fix, with sympathy we burn; Each virtue in each passion takes its turn; And still new needs, new helps, new habits rise. That graft benevolence on charities. Still as one brood, and as another rose, These natural love maintained, habitual those.” source