This article examines the elements of the Seventeenth Century debate about the Cartesian body-machine theory which pitted Abbé Le Moine against Arnauld. Both theologians engaged in specific discussion of the incompatibility or, to the contrary, the compatibility of this theory with the thesis of the substantial union of the body and soul, as well as the consequences of applying mechanical laws to living beings. The origin of the disagreement is first reviewed to then analyse the works of Descartes which are (...) in question and, finally, to evaluate the respective arguments of the two authors. (shrink)