Thinking, Preface, Intention

In the Preface to the Meditations, Descartes explains that what follows is an elaboration of two topics more briefly considered in the Discourse--the existence of God, and the separation of Mind, or Soul, and Body.  Thus, wittingly or otherwise, the text as a whole illustrates a common function of Thinking--the formulation of an Intention, and the execution of it, i. e. its guidance of subsequent processes.  Now, the allusion in the Preface is to part IV of the Discourse, which is preceded by, in part III, a proclamation of unquestioning allegiance to his religion, from which it can be inferred that he accepts the dogma of the theses that God exists and that Soul and Body are separate.  So, perhaps, the two significant previously discussed flaws in the Meditations--1. The abstraction, from the outset, of a contemplative exercise from an act of writing, and 2. The inference from the possibility one's bodily experience is other than it seems to be, to the possibility that one has no body-- inadvertently show how evidence can be tainted by a prior commitment.  Regardless, the common contemporary academic practice of abstracting the Meditations from that Preface only facilitates the misrepresentation of the work as a presupposition-less exercise in Method.