Introduction

Interdisciplinary discussions of theology and science on human identity often center around issues such as personhood, consciousness, and the soul. The exact meaning of these terms is debated, and this creates difficulties around reconciling theological convictions of human personhood with scientific descriptions of the human being. In this article, I employ traditional Christology as a framework for understanding a theological account of humanity. The assertion that Christ is truly and fully human, as espoused in the Chalcedonian Definition, serves as an axiom for understanding the constitution of humanity. Likewise, to make Christology primary in discussing humanity also means to consider how Christological terminology is used to understand both Christ and the rest of humanity. This article thus pivots around the Chalcedonian distinction between personhood (Gr. prosopon/hypostasis) and nature (Gr. physis), as Christ is professed to be a single person in two natures, divine and human.

This distinction is largely ignored by contemporary science‐and‐theology literature, with the consequence that theological conceptions of human identity become difficult to pin down and to relate with science, while also becoming unmoored from doctrinal foundations. Some may argue that traditional Christological terminology is antiquated and not relevant to the contemporary discourse. I argue that a Christologically informed conception of humanity's constitution should take seriously the terminology of nature/physis and person/prosopon/hypostasis. Before one ignores these terms—personhood and nature, and their traditional theological content—it is important to understand the deeper rationale for why classical Christology professes this distinction between personhood and nature at all; that rationale is essential to engaging classical Christian theology with science while preserving the former's doctrinal integrity and internal coherence.

In this article, I first introduce the Christological distinction between personhood and nature. I show how this distinction troubles current science‐and‐theology scholarship on personhood, as human characteristics that are often equated with personhood actually, per this distinction, refer primarily to human nature. This means there is confusion of theological concepts, and this confusion leads to some troubling implications. To address these concerns, I offer a proposal for understanding humanity through the relationship between natural energies (Gr. energeia) and personhood, drawing from the thought of the Eastern Orthodox theologian Christos Yannaras. This proposal presents a view of humanity that is Christologically informed, addresses several of the difficulties present in the science‐and‐theology scholarship surrounding human personhood, and gives a theological characterization of humanity that can be productively engaged with contemporary scientific understandings of humanity.

The Christological Distinction Between Personhood and Human Nature

By claiming that Christ is a single person, but existing in two natures, the Chalcedonian Definition draws a theological distinction between how these two concepts—personhood and nature—can be used to describe humanity. Nature cannot be equivalent to personhood, as that would violate the logic of this confession. That means that characteristics proper to nature cannot be proper to personhood; this creates problems when considering the numerous characteristics traditional Christology applies to Christ's human nature, and not being able to apply them to his person. I will explore the Christological use of both of these concepts—personhood and nature—in turn, to reveal why this Christological distinction is essential to observe.

The Implications of the Person–Nature Distinction for Science and Theology

This distinction between nature and personhood has important implications for the science‐and‐theology discourse around personal identity. If scholars are to address human personhood, whether philosophically or by using scientific research, they should recognize this theological distinction and be cautious about whether they are engaging with aspects of human nature or personhood—and yet, many do not. For example, Richard Swinburne, in arguing against a purely material account of humanity, claims that the soul is the constitutive part of human identity:

I am my soul plus whatever brain (and body) it is connected to. Normally my soul goes when my brain goes, but in unusual circumstances (such as when my brain is split) it is uncertain where it goes. So long as I continue to have thoughts and feelings and purposes, I have survived any operation—whatever happens to any particular physical parts of me. So my soul is the essential part of me—its survival is necessary and sufficient for me to survive. (Swinburne 2009, 507)

Swinburne argues that what constitutes his identity, his essential “I,” is constituted by the soul and its functions: thoughts, feelings and purposes. Consciousness, therefore, is not proper to the physical brain and its functions, but to the substance of the soul. Swinburne's reasoning is an attempt to detach identity and consciousness from pure physicalism, and to assert that “there must be more to me than the matter of which my body and brain are made, a further essential non‐physical part whose continuing in existence is necessary for the brain (and so body) … to be my brain (and body)” (Swinburne 2009, 507). However, according to the above Christological distinction, both the soul and functions of consciousness, regardless of whether they are considered physical or of another substance, are considered parts of human nature, as Christ possessed a fully human soul and consciousness. Thus, soul and consciousness cannot constitute the singular personal identity Swinburne desires, as then Christ would have two identities. Considered Christologically, the soul and its functions are distinct from personhood.

It is likely for this reason, as Mark Harris notes, that some scholars today see merit in Apollinarian arguments that the Logos simply replaces the human soul in Christ, thus constituting his singular identity (Harris 2017, 80)—it can be an easier position to conceptualize than to believe that Christ is the eternal Logos and yet has a fully human soul as well. But traditional Christology has consistently emphasized the full reality of Christ's human consciousness and all that it entails. The conclusion is, as Meyendorff notes, that it is “impossible to identify the hypostasis with the concepts of (self‐) consciousness or of intellect” (Meyendorff 1969, 63). The distinction between personhood and human nature means that one cannot simply ground personhood in any natural characteristics—including the body, consciousness, soul, or will—for such a move would violate the principles of traditional Christology. Swinburne, as well as any scholar who attempts to ground personal identity in the soul, mind, or even the physical body, is neglecting what Christology has revealed about the difference between human nature and personhood. In this way, both sides of the substance dualism‐physicalism debate neglect Christology if they ground personal identity in any aspect of human nature.

To use another example from a different perspective, Niels Henrik Gregersen, introducing a volume titled The Human Person in Science and Theology, proposes a “biocultural paradigm” in which “the human person emerges as a result of the interference between the biological roots of human personhood and the cultural nexus of which any human person is part” (Gregersen 2000, 6–7). Gregersen's view is offered as a corrective to approaches that view the human person as explainable solely by biology and neuroscience, and instead emphasizes both the biological characteristics of humanity as well the importance of cultural influence in constituting personhood (Gregersen 2000, 8). Once again, however, discussion of the biological components of humanity would appeal to the Christological category of human nature, not personhood. Biological and evolutionary sciences can at best account for the origins and functions of human nature and its outworking—but they cannot constitute personhood, for otherwise Christ would possess a human personhood. Psychological sciences, given the above discussion, have the same problem. Even the cultural factors that Gregersen regards as important in fashioning personhood cannot evade this issue—human group characteristics such as culture can also be seen as a part of human nature, as traits that pertain to all humans in an abstract way (Harrison 2003, 208–209). Cultural factors cannot constitute personal identity, for otherwise Jesus Christ's particular cultural milieu and societal upbringing would have to be professed as either shaping a new human person or somehow constituting the eternal identity of the Word of God—and neither option is acceptable to traditional theology.

Terminology is an issue here, as the word “person” can be used in many ways across disciplines: as analogous to “human being” as an entity, or as a specific philosophical construct, or in a theological sense as equivalent to “hypostasis” or “subsistence.” Gregersen's biocultural approach certainly has merits with regard to exploring the many facets of human existence; however, given that “person” is used with a specific meaning in traditional theology, this meaning should be considered when bringing theology into interdisciplinary scholarly discourse. And from a Christological perspective, personhood is not constituted by biological or cultural factors, so Gregersen's biocultural approach is more appropriate to discussions of human nature, not personhood. If traditional theological categories are going to be used in interdisciplinary discussions, then the implications of this Christological distinction should be heeded. Both of the above arguments from Swinburne and Gregersen ground personal identity in characteristics that Jesus possessed in a fully human way—and yet because such factors did not constitute a separate human person in him, these factors cannot be the grounds of personhood.

The conclusion drawn above is not without some implications that are difficult to conceptualize. As noted, it is difficult to come to terms with the idea that Christ possesses a fully human body, soul, consciousness, and will in addition to his divine characteristics, because such characteristics are so intuitively and frequently associated with personal identity. The particular profession of Christ's fully human consciousness and will may make it seem to some as though Antiochene School theology did win the day and the Word of God and Jesus of Nazareth are just completely parallel realities working together. Since this position has been denied, it is then difficult to reconcile how Christ can still logically be a single personal identity while possessing two wills, two rationalities, two sets of knowledge, and two different experiences of passions and suffering. I suggest that these conceptual problems largely stem from the collapsing of the distinction between personhood and nature that is frequently made (if nonconsciously) in the science‐and‐theology discourse: implicitly tying these characteristics to personhood, and then trying to fit them into a theological grammar that properly understands them as characteristics of human nature, creates problems.

If we take traditional Christology and its professions seriously, however, and uphold this distinction between personhood and human nature, one may justifiably have further conceptual concerns. If personhood is not defined by consciousness, will, experiences, or knowledge, then what is it defined by? In other words, if our bodies, minds, souls, and wills are not constitutive of our personal identity, then what are we? And correlatively, what exactly are these characteristics, then, if not us? These are reasonable questions, and the decoupling of personal identity from characteristics of nature prompts a major shift in the way we understand human constitution. What is needed is a Christologically informed understanding of human constitution that starts with personhood and nature as traditionally understood, and then conceptualizes the human being in a way commensurate with those concepts.

A Proposal: Humanity Constituted by Natural Energies

To propose such a Christologically informed conception of humanity that both preserves the crucial theological distinction between personhood and nature while also being able to engage with contemporary scientific understandings of humanity, I draw on another important term used in Patristic theology: energies (Gr. energeia). Although this metaphysical idea is not identical to the modern scientific concept of energies, the etymological similarity does highlight a semblance of a relation between the two concepts—both are concerned with the potentialities, movements, and expressions of things. Energies were understood by Patristic theologians as the actualization of a nature in reality, or the outworking and activity of a nature. Discussion of energies can be seen as a way of asserting that natures are intrinsically dynamic realities, not inert abstractions: there is no nature without movement or energy, for it is the energy that effects the nature in existence. A nature without energies would not truly be a nature at all, for it could not take effect in reality and would thus be entirely abstract and nonexistent. Meyendorff notes that energy is “the concrete manifestation of nature; and the hypostasis gives it its quality or manner of being” (Meyendorff 1969, 111). Thus, when speaking of the relationship between personhood and nature, we can just as easily speak of the relationship between personhood and natural energies. Naturally, traditional Christology professes Christ as having two sets of energies or activities—divine and human.

This can also be difficult to conceptualize, as energy is understood as activities or capabilities; surely this does not make Christ two agents, if his two natures are both active? A helpful analogy for understanding how Christ can act with two distinct energies is provided by the Russian theologian Vladimir Lossky: “One must conceive in Christ at once two distinct operations and a single goal, a single act, a single result. Christ acts through these two natures, as a sword reddened in the fire cuts and burns at the same time. Each nature cooperates in the single act according to the manner suitable to it” (Lossky 1978, 104). Hence, professing two energies in Christ does not destroy the unity of Christ's person, but rather emphasizes the distinctiveness of his natures as expressed through his two active energies: explaining this idea more directly, Lossky writes, “Each nature acts according to its own properties: the human hand raises the young girl, the divine restores her to life; the human feet walk on the surface of the water, because the divinity has made it firm” (Lossky 1957, 146). In this way, Christ remains a single person, but operates in two distinct manners—we thus know his singular personal identity both through his human expressions and his divine actions.

It is therefore useful to think of natures rather in terms of their energies, as it is by their energies that we know natures at all. Such a conceptual move opens new possibilities in thinking about both Christ and humanity. Thinking about Christ in this way, his human nature did not constitute his personhood as the divine Logos, but it did effect that identity into the human world through its own energies. Reconceiving human natural characteristics (such as body, soul, consciousness, knowledge, and will) as energies makes them dynamic actions, not static entities, which may be more palatable to understandings of how Christ could possess two seemingly contradictory sets of natural characteristics. God is not extended in space and time, and yet Christ is circumscribed in a body—but there is no logical contradiction between these two statements if being embodied is an energy, an activity, for Christ is then merely effecting his identity in two different ways simultaneously. Christ is not two sets of consciousnesses, divine and human, but rather Christ expresses himself in two sets of consciousnesses, divine and human (I speak of a divine “consciousness” analogically here, as such a thing would be as qualitatively different from human consciousness as nonspatiality is from being circumscribed in a body). It is as if we should think of these concepts more as verbs than nouns: if natures are inherently dynamic, then we must speak of their characteristics in dynamic and active ways.

What is Personhood?

One possible criticism of Yannaras's ideas, however, is that they characterize personhood in such a way so as it to remove it from scientific inquiry altogether. Personhood becomes a purely theological concept, inaccessible to approach from science. This is what Yannaras intends, as he argues that equating biological and psychological characteristics with personal existence exceeds the metaphysical claims of science (Yannaras 1991, 61–62). But scholars may rightly ask why something that is expressed in reality—as personhood is, albeit through natural energies—cannot be observed, studied, researched, and theorized. Indeed, the idea that energies reveal personhood should offer some bridge between the theological concept and scientific research. Yannaras's definition of personhood above, as the relationship with God that calls a human into being, is not robust enough to answer this issue. Yannaras argues for both personhood's distinction (and thus untouchability) from nature and its ability to express itself through and qualify nature. Elsewhere, Yannaras writes that “Persons and energies are not ‘parts,’ or ‘constituents,’ or ‘passions,’ or ‘accidents’ of the nature, but the nature's mode of existence. The personal expression of every energy recapitulates ‘without parts’ and ‘in the form of unity’ the whole natural energy, just as the person recapitulates the whole nature and is the existence of the nature” (Yannaras [1987] 2007, 58). This is more helpful in addressing how personhood acts as a sort of organizing and concretizing force for nature, but it does not account for Yannaras's insistence on personhood's untouchability by science.

Part of the issue here may be that personhood is a somewhat inherently mysterious concept in traditional theology. David Bentley Hart, while writing on the Chalcedonian Definition and its distinction between personhood and nature, argues that a key element of personhood is its irreducibility to natural characteristics:

The rather extraordinary inference to be drawn from this doctrine is that personality is somehow transcendent of nature. A person is not merely a fragment of some larger cosmic or spiritual category, a more perfect or more defective expression of some abstract set of attributes, in light of which his or her value, significance, legitimacy, or proper place is to be judged. This man or that woman is not merely a specimen of the general set of the human; rather, his or her human nature is only one manifestation and one part of what he or she is or might be. And personality is an irreducible mystery, somehow prior to and more spacious than everything that would limit or define it, capable of exceeding even its own nature in order to embrace another, ever more glorious nature. (Hart 2009, 211)

Hart's explanation reveals some dimensions to personhood that explain why it may be a difficult concept to approach scientifically. For one thing, a person is definitionally unique, and what constitutes a person is definitionally what is unique about them—which, we might note, makes personhood largely unaccountable to science, as a discipline that investigates regularities and patterns. Likewise, if personhood is irreducible to and transcendent of natural characteristics, then the best science can do is approach how personhood is expressed in natural energies—it cannot approach personhood itself. Finally, Hart notes that personhood is a concept with open possibilities: this is seen in Christ, who, while properly a person with a divine nature, is able assume a distinct nature as well. And, as Hart alludes to at the end of the above passage, this openness is seen in humans in deification, in which human beings gain eternal life through becoming “partakers of the divine nature” (2 Peter 1:4 NKJV). In this way, personhood is able to bridge multiple natures at once, even if those natures are of such difference as those of humanity and divinity. Such a concept will resist being too easily definable.

Rowan Williams offers a differently worded, though conceptually similar, take on this issue by saying that personhood is not a “thing” to be added to nature, or a substance in its own right, but rather is an organizing principle. In a manner similar to Yannaras's account of participable knowledge, Williams claims that while we cannot observe personhood, personhood is disclosed through relations (Williams 2021, 125–26). And the foremost relationship that constitutes personhood is that of the person with God:

A Christologically shaped anthropology is thus one that foregrounds the mystery of the ‘personal’, not as a mystique of fathomless and arbitrary liberty or a sentimentalism about the oddities of human psychology, but as a recognition of the centrality of freely responsive action in any account of the human—action that, in responding to the call or invitation of its divine source, acquires an identity that can be declared or exposed in relation to other created beings. (Williams 2021, 127)

In examining these scholars’ views on a Christologically informed conception of personhood, we find that it is a difficult concept to define, and possibly is inherently so—personhood is not a thing that is identifiable by empirical or objective observations, but is rather communicated through relational knowledge. Nevertheless, these thinkers’ comments reveal an essential way in which personhood is important for theology's engagement with science. Although personhood is individually unrepeatable, and thus not abstractable in the way scientific theorizing might prefer, it still expresses itself through natural energies and makes itself known through its relations. These relations include both God and other finite creatures, such that personhood is known and understood both in reference to created beings (and thus within the dynamism of the scientific order) and in reference to God. Thus, in many respects, personhood can be seen as a bridge between divinity and humanity, and thus potentially a bridge between theological and scientific investigations of humanity.

Conclusion

To conclude, I submit that if we want to affirm traditional Chalcedonian Christology, then we need to take it into account when engaging in interdisciplinary dialogue with anthropology and science. Much of the current theological engagement with science does not account for the difference between personhood and human nature that stems from Christology, and as such there is confusion about terms and the grounding of human personhood. By emphasizing these relational and dynamic understandings of Patristic terms, I not only desire to enable science‐and‐theology conversations to find fresh points of engagement with contemporary scientific research, but also to do better justice to traditional theology in such conversations. Beginning interdisciplinary discourse with an understanding of this Christological distinction and its implications could lead to interesting new developments in the science‐and‐theology discussion on human identity, and I have proposed one such idea toward that end with an examination of Yannaras's use of the concept of natural energies. Ultimately, this proposal of seeing humans as dynamic and participable natural energies that express unique personhoods is one that takes traditional theology seriously on the Christological distinction between personhood and nature, and offers some new and interesting paths for engagement with science, even if closing others. My hope is that this article can inspire other explorations of how we can use traditional theology and Christology to reframe engagements with science and potentially find fresh avenues for conceiving of human identity.

Acknowledgment

An earlier version of this article was presented as a short paper at the annual meeting of the Science and Religion Forum, which was held online from May 26 to 28, 2021. The title of the meeting was “Science, Religion and Human Identity.”