Abstract

Among Leibniz’s contributions to the philosophy of mind, two topics bear relevance to contemporary discussions in cognitive sciences: the mind-body problem, and the universal language. Leibniz’s deterministic view rejects inter-substance causality between mental and bodily states, as well as between mental or bodily states of different individuals. In addition, Leibniz believed in the need to enhance communication through a universal language based on symbolic representations. Here I reconsider Leibniz’s ideas in the light of experimental evidence coming from mirror neurons. These recently discovered brain cells, responsive to both action execution and observation, are thought to enable the interpretation of the action performer’s intentions through their representation in the observer’s own brain, thus storing embodied shared representations. I propose that mirror neurons’ cross-modal responsiveness, whereby seeing an action being performed by somebody else triggers similar neural response to that of performing that action oneself, can be interpreted as an instantiation of intersubstance causality. I suggest that mirror neurons’ properties speak not only to the non-dualistic equation, supported by brain science in general, whereby in a given individual, mental states arise from bodily states but also introduce the possibility that bodily states may arise from someone else’s bodily states. In addition, I propose that this automatic embodied flow of information between individuals (from performer to observer) bears relevance to Leibniz’s intuitions on symbols. Specifically, I suggest that the shared representations stored in mirror neurons, thought to enable the interpretation of the action performer’s intentions, may be seen as a biological instantiation of Leibniz’s planned, but never realized, universal characteristic.