A contextual examination of St. Anselm's ontological argument

Marta E. Layton, Cleveland State University


Many scholars, both in the history of philosophy and in contemporary times, have criticized and defended St. Anselm's ontological argument. Much of the work on the subject has evaluated the argument of Proslogion II and III using symbolic logic, and has either focused on presenting what the author thinks St. Anselm was saying in those chapters, or has critiqued the logic of the ontological argument's structure or of the plausibility of its premises. Few authors have looked at how St. Anselm's conception of God in the later chapters of the Proslogion and in the Monologion affect the ontological argument. Fewer still have inspected the way St. Anselm would have been affected by historical events and by the work of earlier philosophers. This thesis aims to examine the ontological argument of St. Anselm, both in terms of why St. Anselm chose to develop it as he did and whether it is logically valid and sound. I will begin by exploring the historical events that would have influenced St. Anselm's thought, such as the hierarchical nature of Benedictine monasticism and the power struggles between the Visigoths and Franks in medieval France. I will then turn to St. Anselm's writings, looking at the theistic proofs he gives in both the Monologion and the Proslogion. In this way I will be able to identify the ontological argument that was advanced by St. Anselm. Having identified the Anselmian ontological argument, I will then evaluate this argument's logical validity and soundness. I will first consider what logical sources from antiquity St. Anselm would likely have had access to. This will allow me to establish the system of logic St. Anselm would have used in evaluating his argument. I will conclude this thesis by critiquing the challenges raised by Gaunilo, St. Thomas Aquinas, and Immanuel Kant to Anselm's argument. This approach makes it possible to evaluate St. Anselm according to the logic he would have known when constructing his argument, and thereby to avoid anachronistic criticisms