This research aims to analyses Leibniz’ Monadologic Ontology and his theory of expression as opposed to those readings of Leibniz’ work that define monads as isolated entities that lack that all possible relation. The analysis will also show that, beyond his notion of Personal Identity, underlies a logic of Otherness able to dialogue with contemporary Personalism. This logic of otherness, if our reading of Leibniz is right, it is especially ostensible in the ‘spirits’, which expressive nature establish not only a (...) systematic bond with the totality of beings that integrate the world, but also a notion of Personal Identity. Such notion allows that otherness acquires a prescriptive character: to place us in other’s situation and thus understand their needs and, through this, acknowledge our place in the cosmos. In order to achieve this we will carry four tasks: first, we will analyze in depth the application of his theory of expression to Monadologic ontology and his notio completa. Second, we will appreciate what implicatures have both for the specific case of spirits, emphasizing the communitarian nature of these rational monads. Third, we will rebuild a Leibnizian theory of Personal Identity and finally, we will compare the results with the main Personalists’ body of thesis. (shrink)