Abstract

The object of this investigation is the constitution of the modern notion of substance on the basis of the concepts – inherited from the late antiquity and themiddle ages – radical contingency / existence, infi nity and representation. The evolution of this constellation of concepts crystallizes historically in the idea ofreality as a structured whole, a specifi cally modern idea that cannot be found as such in previous philosophical contexts. It is then shown that the philosophical project of the modern age consists precisely in the conceptual elaboration of this thought. From Descartes to Leibniz, philosophical thinking thus has toreconfi gure the traditional notion of substance according to the requirements of this new conception. The Leibnizian hypothesis of an irreducible plurality of substances proves to be an essential stage in the historical development of this idea. At the same time, the examination of the internal inadequacies of the Leibnizian articulation of this concept provides instructive indications of its further development in philosophical thought.