The Arabic tradition knew Alexander’s treatises On Fate and On Providence. Alexander criticizes the Stoic determinism with some peripatetic arguments. In those treatises we can find, at least, two positions: the peripatetic and “libertarian” position represented by Alexander, and Stoic determinism. A very similar discussion can be found in Islamic tradition. As S. Van den Bergh has insisted, Islamic theological schools had some Stoic influences. One of the issues in which we can find some common views is, precisely, the problem of determinism and free will. The aim of this paper is to show that the kasb (acquisition)doctrine of the Islamic theologians Asharites is very similar to Stoic determinism in its compatibilist version: both, Stoics and Asharites, conceive a causal network established by the fate or the providence. From this point of view we have to discuss which is the true agent of the natural and human acts that happen in this world. If the providence guides every act, the natural causality and the free will should be denied. On the one hand, I will present some arguments from the most representative Asharite theologian, al-Ghazali, to support a kind of compatibilist determinism; from the other hand, I will evaluate Averroes peripatetic arguments against determinism. Is Averroes more consistent than Alexander or do we have to conclude that al-Ghazali and the Asharites have stronger arguments in order to support the kasb doctrine?