In Defense of Thomistic Ontological Pluralism

There was a phenomenal discussion on Majesty of Reason between Joe Schmid and Trenton Merricks on existence and ontological monism (see here:https://www.youtube.com/watch?v=ZhSnuXDkswI&t=15s). Specifically, they discussed Merricks’ 2019 paper: “The Only Way to Be” (see here: https://philpapers.org/archive/MERTOW.pdf). The paper is very interesting and Merricks lays out some, common, criticism of ontological pluralism and I would like to respond to a few of these points. There was a great response to Merrick’s paper by Byron Simmons, but I would like to respond from a Thomistic perspective. I would still recommend Simmons’ paper, though, as it gives a good summary of the response that many contemporary ontological pluralists give to common critiques of their view (see here: https://philpapers.org/archive/SIMOPA-2.pdf). 

One of the main things that Merricks’ brings up in his paper is a, supposed, dilemma for pluralists: either pluralists accept 1. that pluralists accept generic existence or 2. reject generic existence, which renders ontological pluralism unable to state their own view and, thus, unable to accept it. The first horn of the dilemma raises three problems for pluralism, which Merricks discusses in the paper, while the second horn is supposed to render ontological pluralism to be self-referentially incoherent. 

I’d like to respond by splitting the horns and saying that while no thing actually, by which I mean in act, has generic existence, all things possess a purely conceptual generic existence which enables the pluralist to perform universal quantification, contra Merricks, without being committed to actual generic existence. To elucidate how this works, I’ll make reference to a wonderful collection of essays by Joseph Owens called: “Saint Thomas Aquinas on the Existence of God: The Collected Papers of Joseph Owens” (see here: https://www.amazon.com/gp/product/0873954467/ref=ppx_yo_dt_b_asin_title_o03_s03?ie=UTF8&psc=1). In that volume, Owens has a paper called “The Community and Diversity of Being in Aquinas,” where he explains how St. Thomas masterfully splits the horns of Merricks’ dilemma nearly 800 years before Merricks was born. In the paper, Owens talks about how, for Aquinas, when a thing is judged by a person, a person can abstract the essence of the thing, which are the limits on the thing’s esse, from the thing. This judgment results in two things: 1. the abstracted essence and 2. a purely conceptual, unlimited esse. It is especially important to note that this purely conceptual, unlimited esse results from any judgement of anything. Suppose that there is an apple and an elephant. They clearly have two different essences: one has the essence of an apple, while the other has the essence of an elephant. However, though, when the essence from the two things are abstracted from their respective esses, there is the same purely conceptual, unlimited esse leftover from the abstractions. This is how Aquinas splits the horns of the dilemma. Aquinas can perform universal quantification and say that all things exist, indeed, he can even say that everything generically exists, because all things have the same purely conceptual, unlimited esse leftover when essence is abstracted from esse. One may respond by saying that this purely conceptual, unlimited esse is not enough for the pluralist to perform universal quantification because the thing does not have this purely conceptual, unlimited esse in actuality, but only conceptually. My response would be that this objection only works if this purely conceptual, unlimited esse had no basis in thing, but it clearly does as the thing, in order to exist, must have esse.

Another point worth responding to would be Merricks’ use of a quote by Peter van Inwagen where van Inwagen responds to Bertrand Russell. Here is the quote:

“No, Russell, no! Relations are vastly different from tables, yes, but that’s just to say that the members of one of those two classes of objects have vastly different natures from the members of the other—that the properties of relations are vastly different from the properties of tables. For example relations are, as you say, not in space and time and tables are in space and time. There. When you’ve said that, that’s what you’ve said. Relations lack the property of spatio-temporality and tables have it. That’s an enormous difference between relations and tables, all right… But when you’ve described the radically different properties that relations and tables have, you have not only done everything that is needed to describe the vast difference between relations and tables, you have done everything that can be done to describe it. That’s what describing a vast difference is. Stop trying to do something more when there’s nothing more to be done: stop trying to express the vastness of the difference between relations and tables by saying that they have different kinds of being.”

Here, van Inwagen claims that Russell really has no reason to posit ways of being in accounting for the differences between abstract objects and concrete objects since the difference between these two kinds of things reduces to differences in the properties and natures of these kinds of things. Now, I have no interest in defending Russell, but I would like to give a Thomistic response to van Inwagen’s claim that properties account for differences in things and that there is really no reason to posit ways of being in order to account for the differences in things.

Van Inwagen’s view that properties are all that’s required to account for the differences in things would only be true if properties were somehow prior to or more fundamental than the existence of these things, but this is clearly not so. Van Inwagen’s view only works on a thin or Fregean theory of existence where existence is not a principle of actuality in things, but rather a second-order property of things, but it would not work on a Thomistic view where existence, esse, is the most fundamental principle of actuality in things as on this view the differences in properties and natures in things actually reduces to difference in the limits on these things’ esses. To make this point a bit clearer, if properties ground differences between things and existence is not what, fundamentally, grounds the differences between things, then properties would have to have more conceptual content than existence in order to account for the conceptual distinctions between things, but this can’t be so because in order for these properties to have any conceptual content in the first place they must exist and so existence must be more fundamental than the properties and also have more conceptual content than the properties in order to actualize the properties. If existence had less conceptual content than particular properties, then existence would not have enough power to actualize these properties, so existence must have more conceptual content than particular properties. This entails, though, that the differences between things, ultimately, reduces to the differences in the ways that these things exist, which is the pluralist position. This is also St. Thomas’ position as he thought that the differences between things reduced to differences in the limits on esse between the things. I would also like to note that Bill Vallieclla has a phenomenal paper called “Existence: Two Dogmas of Analysis,” that subjects the Fregean view of existence to harsh, dare I say, nigh decisive criticisms against the view (see here: https://philpapers.org/rec/VALQTD#:~:text=One%20is%20that%20existence%20is,are%20no%20modes%20of%20existence).

In sum, St. Thomas’ ontological pluralism, which is his Doctrine of Analogy, and his views on the fundamentality of existence enable the pluralist to split the horns of Merricks’ central dilemma and properly ground the equivocity in things.