A Comparative Study of Ibn-Sina's Contingency and Necessity Argument and Descarte's Trade-mark Argument

Both arguments emphasize on certainty. Descartes is certain about his own existence and realizes the concept of God within himself and Ibn- Sina is certain about the existence of the reality of being. However their difference is that Descarte's certainty is partial and only includes himself and the concept of God. According to Descartes’ view, the existing reality can be divided into finite (Descartes’ own existence) and infinite (the concept of God with its particular attributes); but Ibn-Sina believes that the reality of being is either necessary (wājīb) or possible (mumkin). The two rational binary divisions are similar to each other. In other words, the Cartesian 'finite' is the same as Ibn-Sina’s 'possible', and the Cartesian 'infinite' has at least the same instances as Ibn-Sina's ' necessary' while they differ in their concept and perspective. For Descartes, the criterion of causality (necessity of having a cause) is the need and incompleteness of the effect (ma‘lūl) and the infinite reality of the cause (‘illat). On the contrary, Ibn-Sina believes that the criterion and the basis for causality (necessity of having a cause for an effect) is being 'possible'.