Leibniz on Subject and Individual Substance

Abstract

We will focus on the theory of complete concept in the philosophy of Leibniz. We will not emphasise the epistemological aspects, but rather will concentrate on the metaphysical implications of this theory. Some questions requiring an answer will be: are there two individual substances of the same kind? What is the nature of a substance that is only possible? What kind of notion has the unactualised possible? What is the nature of the relationship between individual substance and the complete notion? In order to answer these questions, we will present in the first part of the paper the concept of individual substance, in the second part, we will focus on the problem whether the possible objects have or have not a complete concept, and in the third part we will give some additional arguments to support our answer.