泰雅語gaga的字面意義是「祖先留傳下來的話」，透過儀式及日常生活的實踐，它也成為泰雅人重要的文化觀念及社會範疇。過去研究都主張gaga是泰雅族社會除了家族之外最重要的功能性組織，但是在視gaga為「社會組織」本身之同時，研究者卻對gaga的性質有不同的解釋，並有若干未能深入解釋之處。本文嘗試從新的觀點──「gaga為觀念的實踐過程」──來整合過去研究對gaga的不同解釋，並深入探討過去研究所未能解釋之處，進而透過gaga在不同情境的實踐，呈現gaga的多重意涵。透過澄清gaga的性質，將有助於進一步瞭解泰雅族社群的性質，並重新思考人類學理論中對於個人和社會的關係，以及宗教和社會之關係的討論。

　　　　　Previous researchers have suggested that the gaga is the most important form of social organisation in Dayan society. However, they argue about whether the gaga is a form of kinship or a religious grouping. Some aspects of gaga showing high flexibility have not been explained, including the following: (a) an individual can freely choose to join or withdraw from a gaga, (b) one gaga can split off from or combine with another gaga, and (c) several possible relationships can exist between a gaga and a given community. One community can include several or only one gaga, and several communities can together compose one gaga; moreover, it is possible for all of these conditions to appear in succession in one locality. This article tries to resolve the confusion about gaga by clarifying its nature from the Dayan perspective and showing it's ramifications in their ritual practice. I demonstrate that gaga is not really a term identifying a special social grouping as previous researchers had believed; rather it stands for "cultural norms" related to beliefs about the supernatural. In ritual practice, gaga may apply to several kinds of cultural categories, including the commuity, wutux nekis (literally, "one ancestor"), household, person, and now the Christian church. Therefore, gaga applies to both kinship and religious situatuions. In addition, the relationship between the gaga and the community is established through practice and is therefore dynamic. For example, two communities can practice rituals together and function as one gaga; later, they may practice rituals separately and so function as two different gaga. A person may choose to obey the norms of a gaga (as a cultural category) and is free to join or withdraw from a gaga. According to the Dayan's own explanations, gaga has multiple meanings; it refers to norms, regulations and ritual proscriptions, a person's identity or good luck, the words spoken to rutux (spirits), and technical knowledge. In all of these senses, gaga are shared among different groups or learned from different sources. As norms, gaga are shared by all Dayan, but only a particular community is exposed to impurity when one of its members transgresses them. The gaga of sowing and harvest rituals are practiced by members of an individual community. By following ritual regulations and learning the words spoken to rutux, a person may be obtain ability, which is also called gaga. A person shares this sort of gaga ability mainly with members of his own community, his wutux nekis, or his household, although he can also import it from other communities. A dayan's attributes are therefore heterogeneous and cannot be seperated from his social relationships. In addition, some gaga are constructed at particular times for specific historical and contingent reasons, and their validity might not be agreed upon by all community members. The Dayan community is not bounded and easily incorporates outsiders. Membership in a community is defined by conformity with its gaga. Attending rituals, joining community meetings, hunting in the community hunting area, and planting crops in the fields located in the hunting area-all are important criteria for defining one's membership in a community. More importantly, the Dayan do not set up an opposition between the individual and society. Rather, they see members of a community as those who share some common attributes-gaga. By sharing these attributes, social relationships are established. Social relaionships are viewed as internal to a person's identity, rather than external. A person's identity is changed and defined in the processes of learning and sharing gaga. Relationships between the sacred and the secular, between society and its members, are not dichotomized.