The problem of representation of abstract concepts, such as “freedom” and “justice”, has become particularly crucial in recent years, due to the increased success of embodied and grounded views of cognition. We will present a novel view on abstract concepts and abstract words. Since abstract concepts do not have single objects as referents, children and adults might rely more on input from others in learning them; we therefore suggest that linguistic and social experience play an important role for abstract concepts. We will discuss evidence obtained in our and other labs showing that processing of abstract concepts evokes linguistic interaction and social experiences, leading to the activation of the mouth motor system. We will discuss the possible mechanisms that underlie this activation. Mouth activation can be due to re-enactment of the experience of conceptual acquisition, which occurred through the mediation of language. Alternatively, it could be due to the re-explanation of the word meaning, possibly through inner speech. Finally, it can be due to a metacognitive process revealing low confidence on the meaning of our concepts. This process induces in us the need to rely on others to ask/negotiate conceptual meaning. We conclude that with abstract concepts words work as social tools: they extend our thinking abilities and push us to rely on others to integrate our knowledge
