Cartesian Trinitarian Persons

Abstract

This paper explores the nature of Cartesian persons in relation to contemporary Social Trinitarian doctrines. We critically engage with three prominent models of the Social Trinity—those of William Lane Craig, Keith Yandell, and William Hasker—and examine how each defines the concept of personhood. Our analysis identifies the presence of a Cartesian notion of personhood (broadly defined) across all three models, though we argue that each presents unique challenges. Building on these critiques, we advance an alternative understanding of the Social Trinity that incorporates a distinct interpretation of Cartesian persons. Our proposal seeks to resolve tensions within current models and offer a more coherent account of Trinitarian personhood.

The literature on the Trinity in analytic philosophical theology is flourishing as classical theists following the Latin Trinity are vigorously making defenses for the coherence of their view against the burgeoning interest in social trinitarianism. One of the issues that needs illumination in this discussion concerns the nature of the Trinitarian persons, which we take to be central to the discussions on a coherent Trinity doctrine (Howard-Snyder 2009). In the recent social-trinitarian literature there has been an interest in different ways of parsing out a social Trinity using some variant of Cartesianism. We contend that not only are there reasons to give up some of the recent proposals because of their loosening of the notion of the persons, but we gesture toward a different Cartesian model of the Trinity that presumes a distinct way of individuating the persons.

In what follows, we will assess some recent Cartesian trinitarian discussions in three sections (Bracken 2008).1 First, we will lay out a description and defense of a Cartesian notion of persons by considering two ways of individuating persons as Cartesians and show how it lends credence to approaching the Trinity as social trinitarians. Second, we will critically assess three recent social Trinity models that presume a Cartesian notion of personhood. Third, in light of these criticisms, and taking up an alternative way of individuating Cartesian persons, we will gesture toward an alternative model and promising possibility for developing a Cartesian social trinitarianism.

1. A Case for Cartesian Persons

The Cartesian view of humans is roughly described as a view representing what philosophers call soul–body dualism or mind–body dualism. In short, the distinction between soul and body or mind and body is a distinction not just of properties, but of property-bearers. There are two types of property-bearers, what philosophers call substances. These substances are two distinct things that are the bearers of a certain set of properties and the ground for them. The soul or mind is distinctively the bearer of mental events—i.e., thoughts, choices, experiences. The body is the bearer of a different set of properties, namely, properties or events of neurons firing, which is the running of the central nervous system, spatially extended matter that occupies a particular space with boundaries that rub against other bodies. These property-bearers are particulars that exist by themselves (i.e., the criterion of independence, according to a common definition) and instantiate the specified and characteristic descriptive properties of the types of entities ontologically described.2 They are radically distinct and, for most Cartesians, the descriptive events are irreducible to the substance derivatively related (Foster 1991; Hasker 1999; Lowe 2008; Moreland and Rae 2000; Swinburne 1997; Robinson 1982; Cooper 2000; Goetz and Taliaferro 2011; Farris 2015a, 2015b, 2017, 2023; Swinburne 2023; Weir 2023).3 In other words, the soul or mind is the bearer of mental properties (e.g., thoughts, experiences, choices) and these are irreducible to the properties/events of bodies. And bodily events, i.e., neurons firing and spatially extended events that occupy a particular space, are irreducible, while the mental events of which they may or may not be causally related to and derivatively identical.

Yet, the particular Cartesian claim that interests us here, as it impinges on the nature of the persons in the Trinity, is what it is that makes persons persons. With the background of the Cartesian view as a version of soul–body dualism or mind–body dualism, what is it that makes persons the persons they are? The distinctive claim of Cartesians is loosely that the person is primarily identified by the soul/mind as the carrier of personal identity. The soul/mind is the distinctive particular that is the person. This is in contrast to, say, the views of materialists who claim something like the notion that persons are material objects of sufficiently complex sorts with sufficiently complex neural capacities or that human persons just are sufficiently complex animals with a first-person power. This, too, is in contrast to, say, a distinctive Thomist view that persons are the bearers of matter–form arrangements (where form is taken to be an immaterial principle or substance in some cases) that give rise to a set of faculties or powers descriptive of persons with both a first-person perspective and higher-order rational capacities. In the varying sorts of Thomist views, persons are compounds or composites of a complex matter–form or matter–mind arrangement.

The Cartesian claims include a series of the following. Following Descartes, Cartesianism (as a term of art) affirms that it is the mind that is the conscious thinking and immaterial thing. There is an intuitiveness to holding such a view because the nature of mental events are such that they are prima facie transparent to the individual in question and the mediator of knowledge to physical things. It is via the knowledge of the mental events themselves that I have knowledge of physical events. The latter is mediated by the former. Or so the Cartesian argues. This presumes then an immediate entailment from our mental events, namely a dualism of mental events and physical events (i.e., bodily events). These two are intuitively distinct and carry over to the respective and logically presumed particulars of which they describe.

Second, the Cartesian would claim that there is often an entity that underlies the ‘cogito’ or the mental operations of what it is to be me. This is the logical claim. When we are characterizing the events under question, we are presuming something about the particular in question. The particular is the bearer of the properties. And for the cogito, otherwise called the first-person knower in recent analytic treatments, there is an underlying particular that bears the properties of cogito. The thing that is known through the first-person is the set of mental events that are grounded and instantiated by a particular, a substance appropriate to the kinds of properties under analysis.

Third, the Cartesian claim is that the substances (of soul and body) are irreducible and there exists an explanatory gap as to the origins of each. The two parts that loosely describe human beings are souls/minds and bodies. But given the radically distinct natures of each, there is an intuitive distinction that defies the sort of logic that one substance would not only be not described by the other substance, but that one substance would logically originate from the other substance.

The previous set of claims raises the need for a more focused and narrow question about the nature of personhood in Cartesianism. If we were to take seriously the psychological tradition of personal identity that it is the sorts of properties that are both descriptive of mental events, psychological introspection, and phenomenal experience as the starting point for thinking about the person in contrast to the animal tradition as it is often described, then we will be close to a definition of personhood. In fact, for the Cartesian, this is the sort of route taken for arriving at a notion of personhood because of the intimate relation between one’s own psychology, epistemic vantage point, and the metaphysics of persons as things. The presumption is that for one to obtain a sense of what it means to be a person or to meet the basic conditions of personhood requires that one enters into relationship with other persons. This presumes further that one has a concept, arguably, of one’s own self and personhood to enter into what I have elsewhere described as the type of thing that can enter into deep and meaningful relationships with other persons. These conditions then seem to be the right sorts of conditions for describing personhood. Whereas the animalist tradition, arguably, does not. In an animalist view the question of what it is about one’s body, the kinds of properties descriptive of the type of biological organism one is does not seem to come close to answering the question of what it means to be a person if, in fact, the person is the type of thing to enter into deep and meaningful relationships with others and to have the right sorts of mental or cognitive capacities to have those types of relations. The only way to make sense of the animalist tradition of persons may be as it is situated in natural selection, yet this appears to make our relationships a device that contributes to survival in evolutionary fitness, but that does not seem sufficient.

This becomes then an intuitive, common-sense way of understanding persons in general. And many Cartesians who are theists would argue that something of the view that persons just are their immaterial substances is also true of God; namely that God is the type of thing that is characterized by mental events of thinking, making choices, and having experiences. When these conditions are met, then the notion of personhood is also met.

In at least one Cartesian view, and likely the most intuitive way of carving out Cartesianism, it is simply that I am identical to my soul. The soul is the core of me and the carrier of my personal identity. But there remain two questions about the nature of personhood in Cartesianism. An assay of the particular is needed to make sense of the person, and here there are different ways in which Cartesians have cashed out their notion of personhood, which become relevant to the recent analyses given to the trinitarian persons in social models.

It is our contention that when thinking about persons along the lines of Cartesianism that social trinitarianism is the most natural place to develop a satisfying doctrine of the Trinity. This is so for the following reasons. If we take it as apparent that each individual person just is a substantial soul (i.e., an immaterial substance) with the requisite sort of mental capacities and powers then it seems that if we are to take seriously the fact that the persons of the Trinity are just that substantial souls that have the right sort of mental capacities and powers requisite for having deep and meaningful relationships one with the other. Accordingly, then, this takes the approach that persons are substances and we must make sense of how these substances could exist as a unity rather than beginning with what we might take to be the view that God, himself, is a person of the Cartesian sort and approach persons as the sorts of individuals that could exist as one person.

Previously, Joshua Farris has spelled out the rationale for arguing that God is a person (Farris elsewhere refers to this as Cartesian theistic personalism); hence he, God, serves as the paradigmatic model for what we know to be true about ourselves as mental beings and persons. The natural and intuitive relation between ourselves and God furnishes a framework for thinking about God, generally, and the Trinity, specifically. Here is the basic argument.

(1)

If I have direct access to my nature as a simple immaterial being that bears one pure immaterial property, and other beings bear marks or features in similar ways, then it is likely these other beings are simple immaterial beings with complex and abstract abilities and properties.

(2)

I have direct access to my nature as a simple immaterial being that bears one pure immaterial property (given introspection, an enduring I-concept, and self-presenting properties).

(3)

Other beings, namely human beings, bear marks or features in similar ways found in premise 2 (given the principle of credulity or phenomenal conservatism).

(4)

Therefore, it is likely that human beings (on the basis of the principle of charity/credulity) are simple immaterial beings with complex and abstract mental abilities (from premises 1–3; modus ponens).

(5)

If it is likely that human persons are mental simples with abstract and complex properties and there is not a suitable naturalistic explanation for this, then the likely metaphysical explanation is a mental Being (some call God) with abstract and complex abilities.

(6)

There is no naturalistic explanation for this.

(7)

Therefore, the likely metaphysical explanation for human persons is a mental Being (some call God) with abstract and complex abilities (from premises 4–6; modus ponens).

(8)

By logical extension, assuming there is a cause behind humans and the natural world, we have reason (principle of credulity) to think this Being is like human beings because the physical world bears marks or features of a Being with complex and abstract mental abilities (premises 1–3).

(9)

Therefore, we have good reason to think that the physical world points to a Being with a mental nature like the one human beings have as the best explanation for persons. This Being many call God (Farris 2014).

In short, the logical relation is not one of “projectionism” from humans to God, but one that follows from the fact of our common-sense paradigm assumptions about what it means to be persons in addition to the explanatory power (spelled out in terms of abductive reasoning) for the notion that God is a person of which we are reflections. And, if Descartes is right that God is the rational cause of our fundamental natures (both as the epistemic and metaphysical cause), then it would make sense that he would be presumed as the sort of person we reflect because the fact of our knowledge of selves and reality depends ontologically on the cause that makes us who we are.

As a framework for theological prolegomena furnishing the foundations for understanding persons, the present Cartesian framework sets up a foundation conducive to understanding God as a person as analogical to our personhood, but the question needing attention is how it is that we make sense of the analogy given that God is a paradigm for understanding our personhood. What is it that is analogical and what is univocal (if anything at all)? This question is bound up in the more fundamental question of how to understand the ontology of trinitarian persons.

There are a few different ways in which a Cartesian might develop a social doctrine of the Trinity. And most of the versions require, it seems, a loosening of the notion of personhood despite their beginning with the three and trying to make sense of the oneness. Some of these approaches require that one adopt an abstractist view of persons and others require an understanding of persons as divisible entities. After critically assessing these options, we will advance a different understanding of the Cartesian person, which retains the initial notion that persons just are their souls (i.e., where the soul/mind is the carrier and core of personhood), and examine one way (Latinist leaning) in conversation with recent Cartesian social approaches.

2. Social Trinity Models and Persons: Craig, Yandell, and Hasker

2.1. Craig’s Mereological Trinity

William Lane Craig proposes a mereological model of the Trinity, which he and J. P. Moreland initially termed “Trinity monotheism” in their Philosophical Foundations for a Christian Worldview (Craig 2009a). Craig republished this material and clarified it some in the more recent Philosophical and Theological Essays on the Trinity, edited by Thomas McCall and Michael C. Rea (McCall and Rea 2009). The essays in this volume with which we interact are Craig’s “Toward a Tenable Social Trinitarianism”, and his response to Daniel Howard-Snyder’s critiques, “Another Glance at Trinity Monotheism”. We look to this latter essay primarily for the sake of clarifying the pertinent concepts of the former.

Craig begins his essay by providing his definition of social trinitarianism (ST): “The central commitment of Social Trinitarianism is that in God there are three distinct centers of self-consciousness, each with its proper intellect and will” (Craig 2009b, p. 89). Such an understanding of persons broadly fits the notion of Cartesian persons that we proposed above.

After providing a critique of what he terms anti-social trinitarianism, and after discussing Leftow’s criticisms of three kinds of ST—group-mind monotheism, functional monotheism, and Trinity monotheism—Craig turns his attention to defending the last of these, his own model. He further clarifies that his mereological model, Trinity monotheism, “holds that while the persons of the Trinity are divine, it is the Trinity as a whole which is properly God. If this view is to be orthodox, it must hold that the Trinity alone is God and that the Father, Son, and Holy Spirit, while divine, are not Gods” (Craig 2009b, p. 94). According to Leftow, such a mereological model of the Trinity runs into one of three problems: it affirms either that “Only the Trinity is God, and the persons are not divine; Only the persons are divine” or it is reduced to what Leftow termed “Plantingian Arianism” (Craig 2009b, p. 95). Leftow defined this last term as “the positing of more than one way to be divine” (Leftow 2009, p. 66). As Craig notes, such a descriptor tells us nothing about what is objectionable about the model: What is wrong with there being more than one way to be divine? Not only this, but it is unclear in what sense the view is Arianism. Leftow posited that it results in a downgrade of the divinity of the persons, but such a view would only entail a kind of subordinationism. Arianism was the explicit teaching that there was a time when the Son was not, that the Son is a creature. In no way does Craig’s mereological model include such an entailment as Arianism.

Craig goes on to argue that there is nothing particularly objectionable about there being more than one way to be divine. He designates two such ways.

• S is divine if S is numerically identical with the Trinity.
• S is divine if S is a part of the Trinity (Craig 2009b, p. 96).

Now, some may balk at the idea that two ways would suggest that S is less divine than the Trinity. But this does not necessarily follow, per Craig: “it seems undeniable that there is some sort of part/whole relation obtaining between the persons of the Trinity and the entire Godhead” (Craig 2009b, p. 96). Rather, he further comments, “such an account can be very illuminating of their contribution to the divine nature” (Craig 2009b, p. 96). Parts can have properties not possessed by the whole, “and the whole can have a property because some part has it” (Craig 2009b, p. 96). If God the Trinity has the essential property of omnipotence, for example, it is because each of the persons has it, not vice versa. Other properties, on the other hand, are possessed by the persons because God the Trinity has them, such as aseity (Craig 2009b, p. 96).

Craig later provides his well-known Cerberus illustration (Craig 2009b, p. 98). Cerberus, the mythical three-headed canine creature that guarded the entrance of Hades, had “three brains and therefore three distinct states of consciousness of whatever it is like to be a dog... He has three consciousnesses” (Craig 2009b, p. 98). Each consciousness could properly be referred to as Cerberus, and each consciousness is fully canine because they are parts of Cerberus; they are not three distinct dogs. To make this more analogous to the Trinity, each consciousness could even have its own name: “Rover, Bowser, and Spike” (Craig 2009b, p. 98). Rover is fully canine because he is a part of Cerberus, and if Rover were to bite some person, e.g., Billy, then Billy could utter the locution “Rover bit me” or the locution “Cerberus bit me”, and both would be true (Craig 2009b, p. 98). To help better understand how Cerberus is only a single dog and not three dogs, Craig offers an analogy of the soul. Typically, a single soul is equipped with a single set of cognitive faculties, that set of faculties being sufficient to ground the soul’s personhood. One could conceive of Cerberus, and thus God, as a single soul but equipped with three sets of cognitive faculties, each set of faculties being sufficient to ground personhood (Craig 2009b, p. 99). Since each set of cognitive faculties belong to one and the same soul, one could not conceive of them as three souls.

Now, in Craig’s mereological Trinity, it is somewhat unclear what is more fundamental: the divine nature or the divine persons. It seems that he may have in mind that the persons are more fundamental when he makes claims such that the Trinity is omniscient because each of the persons are omniscient. However, what makes this unclear is that there are other properties that are grounded in the Trinity as a whole and possessed by the persons derivatively, such as necessity and aseity. On one hand, the persons seem to be prior to the divine nature, and, on the other hand, the divine nature seems to be prior to the persons. As we see in other models, such as William Hasker’s constitution model, the divine nature—being what constitutes the three persons—is prior to the persons. Craig’s mereological, or compositional, model does not lend itself to clear analysis.

Now, Craig’s understanding of persons, in Trinity monotheism, does not parallel neatly the view of Cartesian persons we outlined above. In Cartesianism, persons just are souls/minds. For a person p, if p is F, then for any soul s; if s is F, then it follows that p is s. But Craig’s Trinity monotheism seems to have problems at this point. In Craig’s model, each of the divine persons is a part of the single soul that is God. There is not a strict identity relation between each person and the soul that is God. For, following Leibniz’s law, if the Father (F) is s, and if the Son (S) is s, then it follows that F is S (identity being transitive). This rubs against the Cartesian notion of persons as souls in a couple of ways. First, in Cartesianism, souls are simple substances. They do not have parts of which they are composed. In the case of the Trinity, wherein the Trinity as a whole is the soul that is God, we have three compositional parts that “make up” God. The soul that is God, in Trinity monotheism, is not simple. Second, Craig’s understanding of persons does not follow the typical Cartesian story, in that Craig claims that God is a soul that is endowed with three sets of cognitive faculties, each being sufficient for personhood. This seems to indicate that it is not the soul qua soul that grants personhood, but rather a particular set of cognitive faculties that grants personhood. In Cartesianism, souls/minds do not have a set of cognitive faculties—properly speaking. Rather, a soul just has a set of basic powers properly respective of the type of thing in question. It is rather unclear, then, what it means for a soul to possess three sets of cognitive faculties. In Craig’s model, it seems that a soul is more than a set of cognitive faculties—this seems to be necessitated if a soul can “have” more than one such set. Perhaps, in this model, a soul plus a set of cognitive faculties grants personhood. But as we have said, for the Cartesian, it is not a soul plus cognitive faculties that constitutes a person, but a soul that just is the person. It seems that, in order for Craig’s model to work, it either (a) needs to abandon the Cartesian view of persons altogether or (b) significantly loosen the Cartesian view of personhood. As it stands, there is not much that is recognizably Cartesian about such a notion of persons. Perhaps there is a better way to construct a Cartesian social Trinity.

2.2. Yandell’s Inseparable Trinity

Keith Yandell begins his journey for a logically coherent doctrine of the Trinity by considering the following seven propositions that must be true for the Trinity to be true. In other words, one must affirm all of the propositions to affirm the doctrine of the Trinity as they comprise what it is that makes the doctrine of the Trinity the doctrine of the Trinity.

The Father is God.

The Son is God.

The Holy Spirit is God.

The Father is not the Son.

The Son is not the Holy Spirit.

The Father is not the Holy Spirit.

There is one God.

Yandell, rather than advancing a case for the Latin Trinity, instead, opts for a version of the social Trinity as a logically coherent way to make sense of the seven propositions listed above. The first move in the case for its logical coherence Yandell argues that we should understand the first three propositions not as the “is of identity”. Following the principle of the indiscernibility of identicals for the persons to contain all the members of G, then they will be numerically identical and propositions four to six will be false. This cannot be.

Each person of the Trinity, according to Yandell, is just that, a person that has intelligence and will (Yandell 2009, p. 153). Each has its own individuality, in other words. And what this presupposes is that each is substantial.

This raises important questions about how all can possess the members of G (God) and remain distinct. Further, it raises the question of how it is that they can all be substances which would seem to entail that the Trinity is a composite of three distinct beings. This raises additional concerns about whether the parts can “come apart”, or the possibility that one substance could cancel out the powers of another substance, or how it is that one substance could act without another acting, which would cancel out or flatten the powers of each substance.

Yandell affirms something akin to Latin trinitarianism, yet the fact that he affirms that each person is an individual substance with “three centers of consciousness” entails an aspect of his thought that requires social trinitarianism. However, he does not go about affirming the doctrine of the Trinity by affirming relative identity or subordinationist views, each of which is replete with problems (Yandell 2009, pp. 154–61).

Two Views on Properties and Individuation:

Ways of being conscious form a natural class that fall under “thinking thing”, in agreement with Descartes, which do not require that one has one constant thought—thoughts can be different and still fall under a resemblance relation that is not the same as those beings that are non-conscious. This is what it means to be a person but provides some latitude for the possibility of individual persons being persons yet one as a bearer of properties that are shared amongst the three.

In Yandell terms the “embedded property view” (EPV), substance and property are not the basic metaphysical categories but rather the “bearer-of-embedded-properties” (Yandell 2009, p. 163).

The other is the properties-as-universals (PAUs) view, which permits that all three are truly God because the fourth is true. In other words, the abstraction to the three occurs at the whole as instantiated by the three. Per Yandell: “The two most natural answers, I think, are ‘four’ and ‘one’: four if you think of each predicative ascription as expressing or referring to its own property, one if you think that only the most specific predicative ascription expresses or refers to a property, and the other three are simply more and more abstract ways of describing that property. In the “four” view, all four propositions are true, and it might have been true that the pillow had a property, and true that it had a color property, and true that it had a color property in the green range, and false that it was chartreuse” (Yandell 2009, pp. 163–64).

Both views of properties and individuation are applied in the following logic to the persons as well as to the divinity of the persons. First, Yandell develops each view of property–individuation to the following and argues for the logical coherence of the propositions given above for the fact of each individual person being the center of consciousness, yet also bearing the self-same individuality as a Divine being. In this way, for Yandell, the Divine being is an individual individuated by a set of properties, and the persons are individuals individuated by a set of properties. The persons and the divine being are each individuals that exist in a necessary inter-dependent relation. Here is the logic:

(T1) For any Trinitarian person P, it is logically impossible that P exists and either of the other Trinitarian persons do not exist.

(T2) For any Trinitarian person P, it is logically impossible that P wills what is not willed by the other Trinitarian persons.

(T3) For any Trinitarian person P, it is logically impossible that P engages in any activity in which the other Trinitarian persons in no way engage.

(T4) The persons of the Trinity have complete non-inferential awareness of one another (Yandell 2009, p. 167).

Yandell further writes,

“That three property-bearers be so related that none can exist without the others seems to me not to be problematic. Using the term “simple substance” to refer to some item says that it is at least a relatively stand-alone individual (for Descartes, God or something dependent only on God). “Complex substance” indicates that the item so described is a composite of two or more such individuals, typically each of which can exist independently. Neither term fits the Trinity. The Trinity is three-property bearers of which (T1)–(T4) are true.” (Yandell 2009, p. 168)

And previously,

“We said earlier that (1)–(3) should be viewed as using the “is of predication”, and thus saying of set G (of properties possession of which is necessary and sufficient for a being’s having the divine nature) that: (1) The Father has every member of G. (2) The Son has every member of G. (3) The Spirit has every member of G.

For PAU, this will say of the Trinitarian persons that they instantiate the set of universals included in G. For EPV, this will say that G lists the properties that must be embedded in something in order for it to possess the divine nature, and each of the Trinitarian persons has every property of the list—each has a perfectly resembling embedded property such that having those properties is sufficient for Deity. So there can be three property- bearers each of which has properties sufficient for being divine. Then, there are:

(4) The Father is not the Son.

(5) The Son is not the Holy Spirit.

(6) The Father is not the Holy Spirit.” (Yandell 2009, p. 166)

It is important to point out that in the property views advanced, PAU and EPV, both see the persons as less fundamental to the whole of which they are each instantiators and provide different ways of reading the indiscernibility of identicals. There of course remains a question about the grounding relation between the divine nature and the divine persons. Whereas the other trinitarian option given earlier may rely on a compositional relation (Craig) and the later view (Hasker) depends on a constitutional relation, the grounding relation in Yandell’s view is less clear. But, with that said, we will not concern ourselves directly with this question here.

Instead, we find Yandell’s model to be coherent and compelling. And, insofar, as there is a way to work out the grounding relation, we believe this is one compelling option that takes seriously the coherence of the persons as Cartesian persons (i.e., centers of consciousness, will, and action) with the Divine nature. However, we have a concern about the nature of persons themselves that we have already alluded to, and by considering this, it will open the door to consider our alternative model, which we will outline below. Whilst we do believe the property–individuation does some work (at least epistemically and possibly with respect to the Divine Being of the trinitarian persons), we think that one should begin with the persons first as a way of analyzing the person–God relationship, which furnishs a grounding relation for both that coherently makes sense of the two individuals in a way that resembles what is found in Yandell. Here is the concern: what if the indiscernibility of identicals does not apply to persons, as Farris has argued elsewhere? In fact, we believe that the principle does not apply to persons and that persons, as in a stronger Cartesian view, are viewed as haecceities. Each person has a haecceity, thus each person is individuated in that way quite apart from their properties, generables, and determinative content. But it is the concrete ground of the persons that we believe supplies us with a place befitting the Divine Being as an individual. We will explain below.

Following the PAU view, we argue that there is a way to discern the Divine Being as the three persons construed as individual haecceities. The haecceity being the sort of primitive thisness not just of natures or “any ol’ thing”, but of substances/subjects of thoughts and experiences. Analyzed in this way, trinitarian persons would require a different assay of the Divine Being from the other views advanced. But it is here that we believe given the primitive nature of the thisness’s of the trinitarian persons, there is a way to make sense of the three individuals as one individual.

Along the lines of the PAU view of properties:

1. Could God be a haecceity that has the generable properties of persons?

2. Could God be generable property of a class that comprises three haecceities?

We will consider these questions and possible alternatives using the notion of haecceity as the way of undertaking an assay of the Cartesian trinitarian persons which denies the principle of the indiscernibility of identicals as the way of identifying the persons.

2.3. Hasker’s Constituted Trinity

In his 2013 monograph, Metaphysics and the Tri-Personal God, William Hasker provides a novel model of a social Trinity.4 Following Cornelius Plantinga Jr.’s well-known essay, “Social Trinity and Tritheism”, Hasker outlines his understanding of the divine persons “as distinct centers of knowledge, will, love, and action” (Hasker 2013, p. 22). This understanding of a person parallels Craig’s and is, at least, broadly Cartesian in orientation. Hasker highlights that this view of persons does not map easily onto the ancient view of what a person is. For the patristic thinkers: “an individual was defined [merely] as a collection of properties” (Hasker 2013, p. 24). As a result, Hasker prefers to refer to the patristic fathers that he sees as inclined towards something like social trinitarianism as “pro-social”, (Hasker 2013, p. 25). He considers the Cappadocians as well as Augustine to be pro-social trinitarians.

Concerning the divine nature, Hasker distinguishes between the abstract and concrete views of natures. In the view of the former, natures are considered to be abstract essences or types that are exemplified by concrete particulars. “To say that a number of objects share a common essence, in this sense, is to say that each of the objects exemplifies all of the properties specified in the essence, and is thereby an instance of the natural kind that corresponds to the essence” (Hasker 2013, p. 51). The concrete view of natures, on the other hand, is best understood in terms of tropes. “A trope is an instance of a property, and as such is not shareable, at least not in the way in which ordinary universals are shareable. Furthermore, tropes as property-instances arguably have causal consequences” (Hasker 2013, p. 52). He further writes, “A trope of the divine essence would, then, be a particular instance of the divine essence, the divine essence as instantiated in a divine being” (Hasker 2013, p. 52). In summary, Hasker considers the social Trinity to be a single trope of divinity that is three distinct centers of knowledge, will, love, and action.

Later in his book, Hasker further describes the relationships of the persons to one another and between the persons and the divine nature. In addition to being distinct centers of consciousness, the persons exist eternally as a communion of persons, further relating to one another via perichoresis, a mutual coinherence with one another. Not only this, but each of the persons relate to one another via the eternal relations of origin—the Father eternally begets the Son and, with the Son, eternally begets the Spirit (Hasker 2013, p. 214). These relations are eternal—in a temporal sense—and causal in nature. There is never a time that the Father is not begetting the Son and that the Father and the Son are not spirating the Spirit, so neither the Son nor the Spirit begin to exist. The Father communicates the divine nature to the Son via his begetting the Son, and the Father and the Son communicate the divine nature to the Spirit by spirating the Spirit.

The divine persons relate to the divine nature by way of the constitution relation. By constitution, Hasker does not mean the relation of material constitution as provided and argued for by Michael Rea and Jeffrey Brower (Brower and Rea 2009, pp. 263–82). Rather, he adopts and modifies Lynne Rudder Baker’s understanding of the constitution relation and employs in service of his trinitarian model. This kind of relationship, per Baker, “obtains between an octagonal piece of metal and a Stop sign, between strands of DNA molecules and genes, between pieces of paper and dollar bills, between stones and monuments” (Baker 2000, p. 27). Hasker defines the conditions for a constitution relationship obtained in the following way:

(i) x and y are spatially coincident at t;

(ii) x is in ‘G-favorable circumstances’ at t;

(iii) necessarily, if an object of primary kind F is in G-favorable circumstances at t, there is an object of the primary kind, God, that is spatially coincident with that object at t; and

(iv) it is possible for x to exist at t but for there to be no object of primary kind G that is spatially coincident with x at t.

G-favorable circumstances, of course, are precisely the circumstances in which an object of primary kind F must find itself at a given time in order to constitute an object of primary kind G at that time (Hasker 2013, p. 241; cf. Baker 2000, p. 41).

One can begin to see how Hasker might apply this constitution relationship to the Trinity. Before he spells out his model, he tweaks the conditions for obtaining a constitution relation provided above, dispensing with (i) and adopting in its stead (i*): “x and y have all their parts in common at t” (Hasker 2013, p. 243). When all of this is applied to the Trinity, the Trinity is understood as follows: “The one concrete divine nature sustains eternally the three distinct life-streams of Father, Son, and Holy Spirit, and that in virtue of this the nature constitutes each of the persons although it is not identical with the persons” (Hasker 2013, 244). Though the constitution relationship allows each divine person to be the same as the divine nature, it does not follow that each divine person is identical to the divine nature. Also, unlike the identity relation, the constitution relation is asymmetrical rather than symmetrical: “if a constitutes b it follows that b does not constitute a. So, if the divine nature constitutes the Father, the Father does not constitute the divine nature, and no identity of the Persons can be inferred” (Hasker 2013, p. 245).

One of the implications we see in Hasker’s model of the Trinity is that the divine nature is technically more fundamental than are the divine persons, though the divine nature never exists apart from the divine persons. If the divine nature constitutes the persons, then it follows that the divine nature grounds the persons. Grounding relations are asymmetric non-causal relations that take on the following form: x grounds y if y depends on x to obtain. When applied to the Son, for example, the divine nature grounds the Son if the Son depends on the divine nature to exist.5 But if the Son exists, then it necessarily follows that the divine nature exists. While some may take the divine nature as having a kind of ontological priority to be problematic, this need not necessarily be the case. Being a grounding relation, the divine nature and the persons also relate to one another via a counterfactual dependence, much like an object does to its singleton set. If S exists then, necessarily, so does [S], and [S] is grounded in, i.e., it existentially depends on, S. Should S ever fail to exist, then so will [S], but if [S] fails to exist, then it follows also that S has failed to exist. So, for example, although the Son would fail to exist if the divine nature were to exist, it also follows that the divine nature would fail to exist if the Son were not to exist.

More important for our purposes, though, is Hasker’s view of persons. Though he describes personhood in broadly Cartesian terms, he, like Craig and Yandell, seems—at first glance—to loosen the concept in order for it to better fit his social-Trinity model. Previously in his book, Hasker points to the phenomenon of dissociative identity disorder to argue for the legitimacy of a single individual grounding multiple persons, wherein persons are understood as personalities, and a personality is understood in terms of a conscious life-stream. In a thought experiment, Hasker posits an individual that “has exactly three distinct personalities” (Hasker 2013, p. 242). He then claims that “the metaphysical underpinning of the human personality is some kind of immaterial soul” (Hasker 2013, p. 242). The following lengthy quote is helpful for us.

“The constituted kind… will be the kind, human personality, the kind exemplified by each of the three personalities in question. The constituting kind… can be understood as the kind, human mind/soul. And the ‘circumstances’ in this case can be spelled out as follows: When the human mind/soul sustains a conscious life-stream (assumed to include appropriate elements of cognition, feeling, and volition), there necessarily exists a human personality. In the present case the soul in question sustains three distinct life-streams, and so there are three distinct personalities.”

(Hasker 2013, p. 242)

Hasker has loosened the Cartesian notion of a person, wherein a person is identical to a soul/mind. For Hasker, a person is constituted by a soul/mind, and the constitution relation seems to be a distinct relation from an identity relation. While this may be the case, this is, at most, only a very subtle departure from the Cartesian notion of persons. If a soul constitutes a person, then a soul grounds a person, wherein “grounds” is understood in terms of existential dependence. Remember, for an existential dependence relation to be obtained, if x depends on y to exist, then, if x exists, y exists. We also have good reasons for thinking that such a relation is also a relation of counterfactual dependence: if x exists, then y exists. If x fails to exist, then so does y. But also, if y fails to exist, then x fails to exist. Applied to souls and persons, we can frame the relation as follows: if a person exists, then, necessarily, a soul exists. If said soul fails to exist, then said person fails to exist. But if said person fails to exist, then it follows that said soul fails to exist. If this is the case, then Hasker’s view of the person-soul relation is not that different from the Cartesian view of persons.

However, there are still some areas of ambiguity. Whereas Cartesians typically understand that a single soul constitutes and is numerically identical to a single person (S1 = P1), for Hasker’s Trinity model, we see a single soul constituting three persons, that is, three subjects that fully share the numerically same constituent. Hasker’s earlier move based on cases of dissociative identity disorder (DID) supposedly provides a basis for conceiving how this could be the case, but there seems to be certain problems with the analogy. Primarily, it raises questions about the relationship between a person and a center of consciousness, as Hasker himself points out: “But while there may not be multiple persons in these cases, it is hard to resist the conclusion that there are multiple centers of consciousness” (Hasker 2013, p. 235). Though many philosophers tend to think that a center of consciousness is simply a person, it may be the case, per Hasker, that such theories and concepts concerning “person, mind, and consciousness” may need to be revised in light of the scientific data (Hasker 2013, p. 235). Hasker rightly points out that the data of DID and commissurotomy patients is highly debated amongst neuroscientists and psychologists, but he does not entertain some of the alternative explanations to the theory that a single mind is supporting multiple distinct centers of consciousness. It could very well be the case that these personalities are not really distinct centers of consciousness at all but different functions that the mind forms in response to traumatic situations. In this case, we could only say that these are functional persons/personalities rather than actual persons/personalities. Such an interpretation seems to be in line with some of the cases discussed by psychologists and neuroscientists who study DID and commissurotomy. While Hasker’s theory and possible explanation are fascinating in their own right, they seem to raise more questions than they answer. Hasker himself says that, in the cases of DID, though there are multiple distinct centers of consciousness there are not multiple persons. But previously, in Metaphysics and the Tri-Personal God, he defines a person just as a center of consciousness. How could a single human mind/soul, which is a single human person, support three centers of consciousness and still be only a single human person? Since the data concerning DID and commissurotomy are highly debatable and likely do not shed much light on conceptions and models of a social Trinity, and since no more is said about how a single soul can constitute three distinct persons, i.e., conscious life-streams wherein a person just is a conscious life-stream, it seems that we must conclude that Hasker, like Craig and Yandell, has likewise loosened the Cartesian notion of personhood to a notable extent. The divine persons in this model still seem to fall short of being full Cartesian persons.

3. Cartesian Social Trinity Alternatives (A Psychological–Social Model)

In what follows, we gesture toward a model. We do so by critically interacting with the three social models expounded above. Further, we build on the logical framework of Yandell, which we take to simply offer a logical way forward in developing a coherent trinity. Yet, we are not convinced that his paper advances an actual model, though we use this language. We depart from Yandell at the point of the individuation of the persons—and by implication, the divine nature. If we were to advance a model, that model would find illustration in the psychology tradition, but it would be a psychological model that is strongly Cartesian. More importantly, we depart from the tendency to individuate the persons through Leibniz’s principle of the indiscernibility of identicals. For us, this principle does not apply to persons because it is not properties (as universals) that individuates. It is a primitive of subjects. This is an important distinction.

We have critically examined three social trinitarian options: the Craig model, the Yandell model, and the Hasker model. We have argued that each has deficiencies due to the way in which each understands the ontology of the trinitarian persons. The Craig model takes an abstractist view of persons that identifies the persons with a set of cognitive capacities that can be loosely described as persons yet not proper parts where the persons are impure parts of the one substance undergirding them. The Yandell model yields a mysterianism that is social but leans heavily in the direction of the Latinist model. The Hasker model begins with a loose conception of persons consistent with a Cartesian notion of persons, but it loosens the notion to accommodate for the possibility of split persons that remain conjoined to one underlying soul as substance. In fact, Hasker believes that we have a potential analogy for this with split-brain cases that give rise to split persons (hence the denial of one form of simplicity and indivisibility so common to the Cartesian conception), which also undermines the absolutist conception of persons found in Cartesianism. But it is important to point out that persons are, generally speaking, identical to their immaterial part—which is where Hasker and the Cartesian traditions agree.

The challenges to Hasker’s model are threefold as we have shown. First, it is not clear in the commissurotomy cases he supplies that it yields an actual divisibility of persons. If it does, then it renders the metaphysical boundaries of persons fuzzy and without metaphysical determination. Second, the analogy breaks down because it is not clear that the split persons actually are constituted by the same substance or two distinct substances. Third, the reasoning for how three persons as divisible consciousnesses could be grounded in one substance remains deeply mysterious.

It is important to point out that both of our proposed alternatives seem to require either a loosening of the absolutist criterion of personal identity with the soul or a mysterianism regarding the persons as individually substantial and constitutive of the one divine substantial soul.

A Cartesian social model begins with the three persons defined as haecceities and tries to make sense of the fact that the divine being is not three substances but one substance in a compositional relation. It may be that, in this view, haecceities apply to the persons and the principle of the indiscernibility of identicals does not, but the principle of the indiscernibility of identicals does apply to the nature of divinity where divinity is an essence of the individual persons. And yet, the nature of divinity should not be construed as a type-relationship as if it fits within a species, but as being qua being. Accordingly, one can, it seems, apply the logic given above by Yandell regarding the universal-as-property view as instantiated by three haecceities. For the sake of clarity in seeing how the present alternative might fit with Yandell’s model when it concerns the properties of each person, see the following once again:

(T1) For any Trinitarian person P, it is logically impossible that P exists and either of the other Trinitarian persons not exist.

(T2) For any Trinitarian person P, it is logically impossible that P wills that which is not willed by the other Trinitarian persons.

(T3) For any Trinitarian person P, it is logically impossible that P engage in any activity in which the other Trinitarian persons in no way engage.

(T4) The persons of the Trinity have complete non-inferential awareness of one another (Yandell 2009, p. 167).

That three property-bearers are so related that none can exist without the others seems to me not problematic. Using the term “simple substance” to refer to some item says that it is at least a relatively stand-alone individual (for Descartes, God or something dependent only on God). “Complex substance” indicates that the thing described is a composite of two or more such individuals, typically each of which can exist independently. Neither term fits the Trinity. The Trinity is three-property bearers of which (T1)–(T4) are true (Yandell 2009, p. 168).

In advancing Cartesianism, it is possible for a haecceity to have generable properties. Persons as minds that are haecceities are simple entities without composition. They do not have parts. In other words, there is a radical form of simplicity that would be akin to the sort of simplicity human souls would have. Interestingly, the simple trinitarian souls would be such that they would have a necessary relation to the other simple trinitarian souls. In this way, the indiscernibility of identicals would apply to each person as a divine entity, but due to the fact that they are simple in a way that includes the property of the other person, we would have something like a transcendental simplicity. This is where the mystery ensues for the persons of the Trinity. How is it that they can be one and three? Comparable to simple souls existing without spatial or temporal parts in a 4D universe, the simple persons exist in relation to one another as one singular entity without comprising a complexity. The logical coherence is simple at one level in that each person shares the same generable property and necessarily exists in relation to the other persons, yet each person remains distinct in virtue of the haecceity that each is.

The present alternative depends on the notion of advanced haecceity. And, as we have seen, this is not the view of all Cartesians, but it is the view of some. Epistemically, it depends on the first-person perspective and a robust perspective. All Cartesian persons have a first-person perspective, which is a distinctive power or capacity descriptive of persons and necessary for entering into deep and meaningful relationships with other persons. The first-person perspective is that capacity that each person has of the self, i.e., it is closely related to the concept of self. It is by way of the first-person perspective that we know of the distinctive particularity of our personhood or self-hood. And, because the person is defined as something of a basic subject of thoughts and experiences, it is by way of this perspective that we arrive at a knowledge of persons, in specific our own personhood.

As a basic subject of thoughts and experiences, there is something about the particularity of the subject that is revealed to the person upon reflecting upon the self as a first-person knower. The immediacy of our access to our own natures is present to us. And, given the simplicity of persons as subjects of experience, there is something about the nature of subjects that undergirds and makes sense of the types of mental events that subjects have.

The haecceity, then, in this view, is a primitive but not just any particular primitive. It is a primitive essence of the subject of thoughts and experiences. It is this primitive that makes sense or explains what it is to be a person. For, as a person, there is something about the nature of the metaphysically simple particular that is not explained by bodies, bundles, or properties, but something that exists that undergirds the mental and bodily events of said persons.

In this Cartesian view, then, trinitarian persons, too, are persons in this sense described. What is important about the nature of these persons is that they have a first-person perspective consistent with the views above that affirm that they are centers of consciousness. But, more to the point, they are subjects of thoughts and experiences. This is where a truly Cartesian view is found.

And, accordingly, if each individual person has a first-person perspective, then each presumably has a haecceity. The trinitarian persons become paradigms for us as Cartesian persons. And, like the trinitarian persons, we too have centers of consciousness and are the basic bearers of thoughts and experiences that make us the kinds of beings that can enter into deep and meaningful relationships. The Trinity is like this too.

And while this alternative sticks closer to the Cartesian conception of personhood than the views listed above, it is met with a mysterious challenge—albeit not one that is a strong concern. This view has the advantage over the others that appear to loosen the notion of personhood too strongly to the point that the nature of personhood becomes a wax nose in the hands of theists trying to make coherent sense of trinitarianism. The present view though, however, consistently affirms the nature of personhood as Cartesian persons, but the difference is that each haecceity mysteriously has the property of divinity that the other persons have. In other words, each haecceity shares in the self-same divinity that the others share in. And this is distinct from an abstractist view of individual persons sharing in humanity as a species because the trinitarian persons are concrete primitives that ontologically share in the other.

Accordingly, whilst there exist three first-person perspectives—hence haecceities—there exists one will-nature by which all three exist. There are three persons that have de-se beliefs that exist by way of one singular shared power. Each person has an existence-dependent relation for their haecceity, yet these existence-dependent relations exist at the level of the primitive substance. The primitive thisness’s serve as property-like for each other primitive thisness, but they are not properly speaking universals. Rather they are held at the fundamental level of primitive thisness, and since primitive thisnesses are one singular simple thing, what we know of the trinity begins to look paradoxical. In this way, the description is social because it begins with the three primitive thisnesses that have their own first-person perspectives, but each haecceity is shared between the other two haecceities. And each wills by way of the power of the other at a primitive level or in a primitive way.

This then does not seem to buttress the social views that affirm either a compositional relation or a constitutional relation between the persons, as if we could divide the persons and the natures along these joints. While both might be useful in motivating conceivable ways, i.e., we could have one and many together, these ways of carving the person-nature breaks down—in the same way that the subject–object relationship breaks down at the level of persons, according to the Cartesian account we have advanced thus far. At the level of persons defined as primitive mental/subject thisnesses, these persons can be described as souls or having souls that are the instantiators of properties, but these are, once again, primitives (i.e., the individual/the particular is a primitive). And, while there may seem to be a de dicto gap between subject and object, there is not a de re gap because subject and object enfold or interpenetrate. Here we have something of an analogy for the trinitarian persons that maintains the one-in-three and three-in-one without invoking the traditional distinction of nature and person.

This sharing has some implications. It means that, like Yandell’s model, the persons are interdependent and necessarily exist together. Each of the persons also has derivative access to the other persons. In other words, each of the persons interpenetrates the other and encounters one another in a perichoretic union. The present view bears marks of similarity to Yandell’s Inseparable Trinity model without entering into a composite or constitutive relationship and thereby staying closer to a conception of Cartesian persons. Similar to all three above-described models, it staves off the standard challenges alleged by social trinitarianism. This avoids the challenge of God being a bigger composed entity of the three. It avoids the issue of divinity merely becoming a property as the natures are concretely three persons that are metaphysically simple and mysteriously, yet not contradictorily, necessarily interrelated. It avoids there being three gods, as seems to be entailed by various social trinitarian models, because divinity is not a genera–species relation of which created entities enter into an instantiation relationship. It bears the hallmarks of the Latinist-like model of Leftow with his time-machine analogy (where one person can exist both outside of time and at three times), but it has the advantage of each person being its own haecceity; therefore, each individual exists as a particular point-like entity at which the other two, mysteriously, exist.

Again, while this is rightly categorized as a social Trinity, it strikingly resembles the Latinist model in a similar way to Yandell’s model but without entering into a compositional or constitutional relation. This we see as a potential advantage over Yandell’s model. Furthermore, it has—at least—one advantage over the Latin model in that it depends on a common-sense conception of persons and demystifies Latinism.

There is a final concern that is avoided. This approach appears to avoid the potential concern of partialism—a concern specifically for Craig’s model—or any compositional model, for that matter. It avoids this because of the simplicity of divinity that mysteriously exists in the simplicity of the persons.