In his letter to Denis Mesland dated May 2, 1644, Descartes proclaims, with unmistakable clarity, that his highly contested doctrine of the creation (CD) of the (so-called) eternal truths arises as a necessary consequence of two fundamental metaphysical principles: the Doctrine of Divine Simplicity (DDS), and the postulate of divine freedom. The present study seeks to elucidate these two foundations, as well as the logical consequence they yield. It does so through the critical lens of Mustafa Sabri Efendi (1869–1954), a traditional Sunni Ashʿarite Metaphysician and the last well-known Shaykh al-Islām of the Ottoman Empire.

Sabri was unaware of Descartes’ invocation of the DDS as a foundation of his CD, echoing a broader lacuna in Descartes scholarship, which often fails to link Descartes’s CD to his DDS despite the thinker’s own statements to the contrary. Closely intertwined with this lacuna is a further scholarly difficulty: the historical incomprehension of Leibniz’s critique of Descartes’ CD, which remains insufficiently accounted for in the literature. This study contends that both oversights can be traced back to the same cause—namely, to a strict interpretation of Descartes’ DDS, which forecloses the possibility of even a conceptual distinction between divine essence and divine attributes in Descartes’ thought.

Against this background, the first section of the present study—building upon, yet extending beyond, the foundational insights of Dan Kaufman’s 2003-article on the eternal truths—seeks to intervene in Cartesian scholarship by demonstrating the plausibility of a weak interpretation of Descartes’ DDS. According to this weaker reading, a conceptual (but not ontological) distinction between divine essence and divine attributes becomes identifiable in Descartes’ work. Through a combination of arguments drawn both from the relevant historical context and from systematic reflection, this essay offers this weaker interpretation as a corrective. On this basis, this essay further proceeds to illuminate how the weak interpretation of the DDS can resolve the longstanding enigma regarding the logical connection between Descartes’ DDS and his CD.

Importantly, this essay draws such a resolution through recourse to analogous debates within the Ashʿarite tradition, Sabri’s intellectual home. As the essay demonstrates, engaging these analogous debates not only clarifies the link between Descartes’ CD and DDS; it also sheds light on Leibniz’s fierce critique of Descartes’ localization of eternal truths in the divine will rather than in the divine understanding. It thereby demonstrates that, contrary to existing accounts, Leibniz’s objections did not rest upon a mere misapprehension of Descartes’ actual position.

If the first section endeavors to reconstruct the hypothetical critique that Sabri would have articulated against Descartes—had he been fully aware of the latter’s adherence to the DDS as the foundation for his CD—the second section turns to Sabri’s explicit critique of Descartes’ second metaphysical postulate: divine freedom. The ultimate result of Sabri’s investigation is a conclusion profoundly at odds with contemporary characterizations of Descartes within the history of philosophy. It is precisely Descartes’ relentless pursuit of internal consistency—coupled with what Sabri calls his unreaonsable “reverence for God’s power”—that, in an ironic reversal, threatens to undermine all of his modal conceptions. Thus, through the lens of Islamic rational theology, the present study demonstrates how Descartes’ unyielding commitment both to the logical demands of his DDS and to the theological affirmation of divine freedom compels him to embrace the CD—and how this unhesitating willingness to bite the bullet has fatal consequences for his entire philosophical edifice.