Muhammad Sami


Descartes is usually seen as a thinker who does not employ and preconceived principles in his system without establishing them first through his method. Through an analysis of the development of his notion of certain knowledge, I highlight his reliance in the development of such a principles on principles that he borrows from scholastic philosophy. These principles are unjustified and unjustifiable through his method. I argue that, on Descartes's own terms, this notion should fail. Indeed, this is what happens over the course of the one hundred and fifty years following the publication of Descartes's Meditations. I provide the conclusion that Descartes ends up with a notion of certain knowledge of truth that is psychological rather than ontological and ask whether the loss of an ontological commitment to truth is related to his unjustified rejection of substantial forms.


Philosophy Department

Degree Name

MA in Philosophy

Graduation Date


Submission Date

July 2017

First Advisor

McIntyre, Robert W,

Committee Member 1

Belo, Catarina

Committee Member 2

Fincham, Richard


41 p.

Document Type

Master's Thesis


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Institutional Review Board (IRB) Approval

Not necessary for this item


The completion of this thesis could not have been possible without numerous efforts of multiple institutions, and people. Tabah Foundation helped me in several ways;. Its CEO Mr. Noureddin al-Harthi and its Director of Research Mr. Maan al-Dabbagh were generous enough to provide funding to my study program. Dr. Karim Lahham helped me locate an vital turning point in the history of philosophy which later became the subject of my thesis. Hassan Spiker provided me with comments on my thesis draft. All of this would not have been possible if it was not for Tabah’s Chairman al-Ḥabīb Ali al-Jifrī who recommended me to the institution’s management. The American University in Cairo is where I started my higher education as an undergraduate student in Mechanical Engineering. Its liberal arts education allowed me to explore disciplines that I could not have possibly explored otherwise. It is because of AUC that I was able to discover my interest in philosophy. I will forever be indebted to AUC as in institution, especially its philosophy faculty. Dr. Steffen Stelzer’s inspiring lectures and the kind of questions they raised forced me to appreciate that there is more to philosophia than the scholasticism that was my only focus when I first joined the program. Dr. Robin Weiss devoted tens of hours of her precious time to helping me read and understand some of Aristotle’s passages. Dr. Alessandro Topa helped me navigate my way through this program and decide which courses to take and what topics to focus on given my own interests. As a thesis supervisor, Dr. Robert McIntyre asked me the most challenging questions that made me feel –several times– that might project might actually fail. These challenging questions are the reason why my thesis ended up as a piece that I am truly proud of. I am also grateful for his acceptance of what I now consider a lousy proposal. My thesis readers Dr. Catarina Belo and Dr. Richard Fincham provided important comments on my thesis draft and during my defense upon which I made corrections that changed my thesis to the better. I thank the three of my committee members for an experience that helped boost my confidence in the kind of research I intend to pursue in the future – God willing. Over the past year and a half, my intellectual life was enriched through discussions with Hussein Barrada, Sarah Hammad, Isa Kundra, Wassim Sabry and Mohammed Shafie, all of them colleagues in the philosophy department.