Yujin Nagasawa casts his work in the middle of a protracted discussion over the interpretation of Anselm of Canterbury’s ontological argument. However, this study is not intended as a defense of Anselm’s arguments. Instead, Nagasawa addresses perfect being theism more broadly, understanding it to mean that “God is the being than which no greater is metaphysically possible” (41). Frequently, this concept is connected to a deity who is omniscient, omnipotent, and omnibenevolent. He positions his work as a defense of monotheism across religious traditions, including Christianity, Judaism, and Islam (though he scarcely draws from the sacred texts of these traditions, especially Islam). Nagasawa traces a historical genealogy of perfect being theism beginning with Plato and ending with Proclus, effectively dislodging his argument from any specific confessional tradition.
Nagasawa reformulates perfect being theism to develop an alternative to the omni-God thesis described above. In his “maximal God thesis,” Nagasawa defines God “as the being that has the maximal consistent set of knowledge, power, and benevolence” (2). He is interested in a minimalist claim, urging that the omnis be set aside as undemonstrable. “The Bible talks about God’s knowledge, power, and benevolence as though God has these properties to a significant extent,” he contends, “but nowhere does it say explicitly that God is omniscient, omnipotent, and omnibenevolent” (92). Dismissing the older great chain of being (though he attempts to rehabilitate it later in the chapter), Nagasawa opts for a radial model, allowing for multiple chains of being in which “God is the being than which no greater is metaphysically possible by virtue of occupying the top link in all local chains of being” (60). God is comprehensively great because God possesses all absolute great-making properties to the greatest possible extent.
Part 2 of the book focuses upon arguments contrary to perfect being theism. The first portion unfolds latent assumptions related to the omni-God thesis and perfect being theism. Nagasawa clarifies that “the overall greatness of God, as the being than which no greater is metaphysically possible, also corresponds to His individual great-making properties, such as knowledge, power, and benevolence (81-82). These are all understood to be necessary. Nagasawa identifies three primary arguments against perfect being theism: that God’s properties are internally incoherent (the omnipotence paradox); that God’s properties are mutually inconsistent (the omnis conflict with each other); and that the omni-God thesis is inconsistent with reality (evil exists). Rather than address each of these lines of arguments, Nagasawa maintains that the maximal God thesis undercuts them all simultaneously. Equating perfect being theism and the omni-God thesis gives life to these critiques. The subsequent chapter builds by dealing more specifically with challenges to the maximal God thesis, organized around larger categories of great-making properties, monotheistic aspects of perfect being theism, the problem of evil, and philosophical method.
The remainder of the book is constructive. The bulk of chapter 5 is consumed with a response to Peter Millican, intended to show that in refuting the ontological argument the critic makes greater philosophical assumptions than they pretend. In his refutation, Millican advances the idea of superiority of existence, which states that a nature that is instantiated is greater than one that is not. For Millican, Anselm’s argument fails because it does not necessarily prove the existence of God. But the greatest possible being is susceptible to various interpretations. Nagasawa focuses upon the superiority of existence as something foreign to Anselm’s thought. Millican’s argument is further flawed because of the definition Anselm gives to God as having a nature of which nothing greater can be thought. Nagasawa appends to this that existence is a great-making property so that an instantiated nature is greater than one that only exists conceptually. The chapter constitutes a debate over how to interpret Anselm and the utility of Anselm’s thought for modern philosophy.
From there, Nagasawa responds to parody objections to the ontological argument, beginning with Gaunilo and continuing to his modern imitators. A parody objection is an attempt to construct an argument similar to the ontological argument, showing its absurdity by demonstrating that it could be used to prove the existence of anything. Gaunilo’s lost island argument is likely the most famous and certainly the easiest parody objection, but they all function similarly. In Gaunilo’s case, using Anselm’s logic, the greatest possible island must exist because it can be conceived of. Parody objections collapse ultimately because they make faulty assumptions that are not part of the original argument. Thus, they are no longer truly parallel discussions. If they were, Nagasawa concludes that parody arguments actually become the ontological argument ironically.
The final chapter discusses the maximal God thesis in the context of the modal ontological argument in order to build a positive case for perfect being theism. The modal argument reduces to the claim that “the existence of God is either necessary or impossible” (182). According to the working definition of God in the modal ontological argument, it is not simply claimed that God exists, but that God must exist as a logical extension of the definition. All of this hinges on the possibility premise—the belief that it is possible that a maximally great being exists. After surveying earlier attempts to support the possibility premise, Nagasawa offers his own solution in the maximal God thesis. It is not difficult to see how a maximal God is easier to make plausible than an omni-God. Nagasawa comments that “the maximal concept of God is by definitioninternally coherent because its components are mutually consistent (and internally coherent)” (204). Nagasawa concludes that the strength of the ontological argument can be restored through the maximal God thesis.
Nagasawa’s work is an impressively erudite and provocative study. The arguments are concise and clear, even when technical. Confessionally driven theologians will likely take issue with Nagasawa’s claims. Is a maximally great God really a perfect being? Too much might be given up here. As a work in the philosophy of religion, it makes an important contribution to a debate extending back almost a millennium.
David Barbee is Assistant Professor of Christian Thought at Winbrenner Theological Seminary.
David Barbee
Date Of Review:
April 11, 2018