According to Malebranche, the primacy of the order paradoxically leads to an interrogation about the role of chance. Fenelon and his successors are searching for a means to demonstrate the order of the world. As Polignac at the same time, Fenelon chooses order against chance which is "a blind and fortuitous combination of the necessary and irrational causes". The whole methodology of his Démonstration de l'existence de Dieu consists to establish the necessity of an extra-society cause - God - against a randomly development of internal causes in the universe. In the same logic, Polignac describes materialism as a production of life from the material, as a spontaneous generation of the set of "the living beings appeared together", accidentally organized. Polignac proposes the formalization of an anti-materialist determinism, in order to exclude chance in the appearance of life and in the development of living species. The alternative between chance and God reveals incapacity to imagine models reporting of the embryogenesis of living beings, of their development; incapacity to give a rational explanation of the appearance of species.
