Yet, in the 'best of all possible web pages' Monads can well afford not to have windows: They know anyway what is going on elsewhere, or atually, they have always known it. (By means of that 'PrestabilizedHarmony?' Leibniz avoids the problem to explain how mind affects matter and vice versa. "Car je ne trouvois aucun moyen d'expliquer comment le corps fait passer quelque chose dans l'ame , ou vice versa, ny comment une substance peut communiquer avec une autre substance creee." Systeme Nouveau de la Nature etc.(12). Descartes' followers had introduced the "Systeme des Causes occasionelles" to solve the problem: God creates movements according to our will to move, and thoughts according to movements of exterior things. The idea of a God permanently busy to maintain the harmony of the universe seemed much less attractive to Leibniz then the harmony established once for all. --- )
Gottfried Wilhelm Leibniz (1646-1716) was a philosopher, scientist, mathematician, diplomate and lawyer. Independently of Isaac Newton he 'invented' the infinitesimal calculus (and also the notation df/dx still used.) His philosophical contribution to metaphysics is based on the Monadology, which introduces MonaDs? as 'substancial forms of being. They are a kind of spiritual atoms, eternal, indecomposable, individual. In the way sketched above the notion of a monad solves the problem of the interaction of mind and matter that arises in Descartes' system, as well as the individuation that seems problematic in Spinoza's system, which represents individual creatures as mere accidental modifications of the one and only substance. The "theodicee" claims to justify the apparent imperfections of the world by its being optimal among all possible worlds.