…Obsolescence is relevant.  That is, if a huge gap opens up between the law and the moral order of society, one or the other must change or law risks becoming irrelevant.  This “gap” also has profound significance for the legitimacy of the law. The very legitimacy of the law and even possibly the legitimacy of the legal system and its institutions (e.g., the courts, the legislature, the government) will be undermined if the law becomes obsolete.  Thus, if legal marriage deviates profoundly from social understanding of marriage, both the institution of marriage and society in general are harmed. MORE