Une théorie des universaux pour la psychologie.

This thesis reformulates the philosophical problem of universals in view of an appropriation by psychology and, as a solution, identifies a fundamental distinction between two types of one-to-many relationships: the local-global relationship and the particular-general relationship. The argument is developed in two sequences. First, the epistemological, ontological and historical importance of the problem of universals is outlined through an uncritical review of some classic philosophical writings, followed by an overview of certain relevant facts in physiology and psychology. The second sequence establishes a rudimentary ontology and presents a psychological theory of universals using the notion of depth as a source of examples. The central element of the proposed theory is the local-global/particular-general distinction: local-global characterizes situations where many (local) events have as a common and necessary consequence only one other (global) event, such as when parts belong to a whole; particular-general concerns situations where many (particular) events share a resemblance that collects them into a (general) group, such as when elements belong to a class. The local-global and the particular-general are very different relationships, yet they complement each other and universals are presented as ultimate results of interactions between these two relational modes of events. Finally, the thesis concludes that there is an absence of evidence concerning singularity, but nevertheless proposes three ways to maintain its plausibility