Abstract
In this paper, I will claim that we need two distinct concepts to understand how bodies and things interact. Such concepts are “material engagement” and “mediation”. In the text, I will show that, even if they foster the idea that cognition is not just in the head, nonetheless they are different for what concerns the ontologies they refer to. Material engagement presupposes a defined agent that can be more or less extended, while mediation aims to explain how the agent is defined in the first place. An analogous situation is present in the cognitive science debate, where the extended mind hypothesis and enactive cognition differ for the same reasons. After showing the differences, I will try to justify such an interdisciplinary comparison by referring to the role of the contextual environment as a constitutive element of cognition. At last, I will propose the concepts of temporality and sensorimotor allopoiesis as valuable resources to detect the threshold generating the gap between material engagement and mediation, as well as extended mind and enactive cognition.