The results from categorization studies, both in children and adults, often seem contradictory. My aim in this article is to show that we can solve these apparent contradictions if we take a pluralistic frame. I will refer more specifically to two ways that lead us to taxonomic categories, the perceptual one and the thematic one. If there are two category construction mechanisms that intervene together and if their importance varies across different types of categories, we can advance new developmental hypotheses regarding the acquisition and the decline of category knowledge.
Keywords: categorization, domain specificity, development, ageing