A very formalistic, legal positivist approach has been the dominant method to jurisprudence in Korea. By using Korea's Constitutional Court decision against an anti-out-of-school classes legislation (課外禁止) handed down this year and another against a Civil Law ban on a marriage between broadly defined family members bearing the same family name and the same place of origin (同姓同本禁婚) in 1997, a strong criticism is made to such a legal positivist approach by way of developing a social science based method to jurisprudence while exposing limits and pitfalls of the legal positivist approach. Our argument is that scientifically conducted research data including social science research based ones are not only useful but also necessary for jurisprud...