Plurality of science and rational integration of knowledge

Most scientists who are willing to articulate knowledge from different sources, for example to solve problem set by the society, are confronted daily with the heterogeneity of scientific approaches and with the need to solve increasing difficulties in combining knowledge from various scientific areas. But these difficulties may be set aside when the phylisophy of science postulates the possibility of establishing a priori rational principles of a unified science. Inso doing it logically considers that the problems encountered in integrating scientific knowledge from different sources result from institutional gaps or organisational failures, or from the lack of researchers'skills. the analysis of these problems is consequently handed over to the sociology of science. Therefore, the debate on the unity of science may conceal the value of approaches based on an epistemological regionalism to support the rational construction of knowledge. Due to the heterogeneity of research programmes that coexist within each discipline the integration of scientific knowledge in an epistemic situation that needs clarification. Through short examples taken from social sciences and ecology, this chapter aims at showing how the formalisation of the plurality of scientific approaches may help to overcome difficulties encountered by researchers in getting an oveview of the existing scientific knowledge, in integrating their approaches and in securing the recognition of the quality of their results.