The aim of this study is to clarify the relation between Husserl's phenomenology and psychology. Although Husserl pointed out a similarity between phenomenology and psychology, he did not suppose an identity between the two disciplines. Psychology is a science of facts and phenomenology is the basis to understand the sense of those facts. Psychology may be considered as an autonomous science that studies the psyche through the behavior. But the interpretation of the signification that underlies the behavior can only be made by eidetic psychology. Eidetic psychology, based on the phenomenology, would conduct the depuration of the naturalism that impregnates empirical psychology. According to Husserl, psychology does not need methodological advices from the sciences of nature and must find his own way to understand the sense of the human act. Thus, what psychology needs is a "plus ultra" connecting the psychological investigation with the transcendental.
phenomenology; psychology; epistemology; ontology