In his reflections on the Cartesian philosophy Leibniz proposes that action rather than thought is the essence of the substance. The action of the substance consists not only in thought, but also in spontaneous motion. By means of this new criterion, Leibniz overcomes the Cartesian distinction between corporeal and spiritual substances. Moreover, he overcomes the Cartesian opposition between subject and object by emphasizing the intentionality of thought through the addition of the principle 'varia a me cogitantur' to Descartes' 'cogito, ergo (...) sum'. In the course of this paper the main characteristics of the monad - action, unity, perception, appetition, apperception - will be presented. (shrink)

Originally presented as author's doctoral thesis. Universitèat, Mèunchen, 2011.

The question of the possibility of a world-constitution by logical analysis is exemplarily investigated for two philosophers. Both of them try to the same extent to solve the problem in the context of a universal method founded on the basis of formal logic, while each of them follows opposing aims: on the one hand the foundation , on the other the elimination of metaphysics by logical analysis of language. Following an exposé of the fundamental philosophical and epistemological theses of the (...) two philosophers, the question is answered by treating three partial problems: the so called basic problem , the main problem of the constitution of objects , and the problem of the possible worlds. (shrink)