The Decline and Fall of the Roman Empire · ¶182

The freedom of love and marriage was restrained among the Romans by natural and civil impediments. An instinct, almost innate and universal, appears to prohibit the incestuous commerce of parents and children in the infinite series of ascending and descending generations. Concerning the oblique and collateral branches, nature is indifferent, reason mute, and custom various and arbitrary. In Egypt, the marriage of brothers and sisters was admitted without scruple or exception: a Spartan might espouse the daughter of his father, an Athenian, that of his mother; and the nuptials of an uncle with his niece were applauded at Athens as a happy union of the dearest relations. The profane lawgivers of Rome were never tempted by interest or superstition to multiply the forbidden degrees: but they inflexibly condemned the marriage of sisters and brothers, hesitated whether first cousins should be…

Edward Gibbon · Project Gutenberg #734 (Milman edition) — public domain
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