The thesis is an anthropological study that focuses on the process of identity construction of marginallzed knowledge in the realm of health. The case study is an establishment of spirit mediumship in Chiang Mai Province which invents its ownknowledge within the broader context of health crisis and power relations of many types of discourse concerning health. In Thai society, western medical science is adominant discourse whose discursive practices have marginalized any other sets of knowledge both directly and indirectly. The direct pressure has been made to hindernon-scientific types of knowledge from the process of knowledge circulation. It alsoobstructs marginalized discursive practices in term of delegitimating their explanationsabout the causes of illness and healing process. Moreover, the pressure has been exertedthrough other types of institutional structure such as laws and public health offices ofthe states. These institutions treat scientific knowledge as legitimate, accurate and absolute.The indirect pressure is to communicate to members of society that non-scientificknowledge is irrational, superstitious or inaccurate. The community of spirit medium under study is an example of marginalized knowledge.The study focuses on its discursive practices which incorporate and articulate with varioustypes of knowledge. Its cosmological explanations correspond to its healing practices. Types of sickness under treatment here often happen to be ambiguous when treated under the dominant discourse, for example, certain chronic illness which cannot be cured by scientific means or certain types which have been refused to be treated. Together we call them here as "dregs of hospital." Apart from articulations at the level of ritual and other healing procedures, I will also emphasize the articulation of knowledge of the body of the sick who has experienced various types of treatment. The healing process of this community is going on under the alternative types of cosmologywhich has its own perception about cosmos, man, sickness and death. These results in its specific forms of healing which combine methods that do not depend on external curing techniques, but rather rely upon other types of knowledge which already exist in the belief systemof the individual, especially Buddihist concepts such as ~i~bKarma~i~b, soul and its other syncretic components like animism and the belief in hinduist "~i~bDeva~i~b". There are two major findings of the study. The first focuses on the identity of marginalizedknowledge that can deal with various dimensions of human suffering. Its strong point is the capacity of explanation which combines bodily dimension with spiritual one. The commonfaith of the community has resulted in gradual changes in both the individual's perceptions and their life style. The second finding focuses on power relations of many types of knowledge. In Thailand,"spirit medium" has been marginalized by both the scientific discourse and by official Theravada Buddhism. In the community practices, the reverse of power poles has been found.People who used to belong to the two types of dominant discourse, when faced with health crisis, have accepted to be incorporated into the discourse of this community. Therefore, thereare two pairs of knowledge articulations, first, western science and occultism and second, official Buddhism or intellectual Buddhism and occultism. However, the pairings are notexclusive. In practice, we see the complicate mixture of these knowledge, sometime theysupport one another or sometime, conflicting with one another. These combinations alsoshift in changing contexts. Another important finding related to the above conclusion is the formation of " the community of faith". Its underlying cosmology binds the individual?s life with the othersthrough an invented concept called "~iSai Sanya~i" ( Sai = cord or vein

Sanya means memoryaccording to Buddhist terminology). The word actually delineates the networks of ~iKarma~irelations that stretch over the time span of past, present and future lives. The belief in suchconcept helps create collective spirit and finally leads to the constructions of an "imaginedcommunity" whose members are bound together through past live's connections. Amidst the drastic socio-cultural change we witness, the revival of local knowledge,the rise of new mode of explanations and the articulations between them in various timesand places. There is not any set of knowledge that is able to remain fixed or unchangeablein changing circumstances. The study points out that any set of knowledge will have thecapacity to face with new problems if it shows the flexibility and readiness to adapt, changeor articulate with other set of knowledge. The case of this community reflects the complexityof health problem which cannot be dealt with by any single set of knowledge. There is a necessity to open new social space for diverse types of knowledge and to perceive healthproblem in relation with cultural system.