An Incomplete Liberal Argument Against Incest and a Complete Natural Law Argument In Favor of the Natural Family
William Saletan is wise to find an argument against incest even when "both parties are consenting adults and the genetic rationale is bogus" — Incest Is Cancer. He cites a German court decision stating,
- Incestuous connections lead to an overlap of family relationships and social roles and thus to a disturbance of a family bereft of [clear] assignments. … Children of an incestuous relationship have great difficulty finding their place in the family structure and building relationships of trust with their next caregivers. The vital function of the family for the human community … is crucially disturbed if its ordered structure is shaken by incestuous relations.
- Liberals tend to recoil from such arguments. They fear that a movement to preserve the "family unit" would roll back equal rights for homosexuals. But that doesn't follow. Morally, the family-structure argument captures our central intuition about incest: It confuses relationships. Constitutionally, this argument provides a rational basis for laws against incest. But it doesn't provide a rational basis for laws against homosexuality. In fact, it supports the case for same-sex marriage.
- What is certainly at stake is the natural relationship between parents and children. Children, even if they are loved and raised by those who are not their biological parents, want to know who their parents are, who are their natural family. The fascination with genealogical tables and the opening of adoption records are evidence of this desire to find oneself in a biological succession of generations. No honest “study” has disproved what we all know. Stable marriage between a husband and wife has safeguarded their children, surrounding them with familial love and creating the secure foundation for human flourishing. This natural desire, already weakened in a seemingly more and more promiscuous society, will no longer be privileged in civil law. It will be no more “normal” than any other “family” arrangement. If the nature of marriage is destroyed in civil law, the natural family goes with it.