The brain is a physical organ that transcends the machine-like regularities of mechanics, and thereby reveals that mechanism never was the whole story even about atoms and molecules.
Keith Ward¹

What manner of thing [soul] is would be a long tale to tell, and most assuredly a god alone could tell it, but what it resembles, that a man might tell in briefer compass.
Plato, Phaedrus 246a

So it is with the resurrection of the dead. What is sown is perishable, what is raised is imperishable. It is sown in dishonor, it is raised in glory. It is sown in weakness, it is raised in power. It is sown a physical body, it is raised a spiritual body.
1 Corinthians 15:42-44a

Resurrection Provokes the Development of the Concept

As the earliest Christians try to make sense of the resurrection of Jesus and their own hoped-for resurrection, a greater differentiation of terms and concepts begins to appear, but the biblical terminology is by no means consis-tent.² For example, while soma (normally, “body”) may have been a fairly consistent term of continuing identity for Paul, in Matthew, Jesus says: “Do not fear those who kill the body (soma) but cannot kill the soul (psyche)” (Matt. 10:28). Where the Old Testament, especially the Deuteronomic writings, focuses more on a promised land and on flourishing in this life, in the New Testament, the promise of eternal life is already stimulating a more differentiated anthropology. While this incipient anthropology is not systematically developed in the Bible, it has been frequently addressed from patristic times to our own, as Christians have attempted to understand the relation of body, mind, soul, and spirit, and eventually how they might be personally unified in a continuity that begins in this life but does not end with it.

Generally, the tradition has at least agreed on the importance of the body, for neither Judaism nor Christianity has ever disparaged the significance of this present life; instead, the relationship with God is always developed historically and communally by embodied souls. From Old Testament emphasis upon dealing justly and mercifully with all, especially the poor, to the New Testament care for and healing of the sick, feet washing, and the supreme sacrifice of dying for others, the treatment of the body is an important focus. However, it is never an exclusive focus, for the immanent things of the creation exhibit an inherent openness to the transcendent purpose of the Creator and to a world beyond this one. Hence, our understanding of the soul must be flexible enough to handle the import of our embodied lives in history, our lives as history, and to account for a transformed life after death.

Because of the complexity of these demands, Christian thought, which has shown more or less agreement about the importance of the body, has ranged broadly on everything else, e.g., mind, soul, and spirit, associated with our embodied being. Once again, Christian solutions have generally insisted upon a continuing relation to the body, for such is the import of resurrection as opposed to immortality. Resurrection recognizes the break of death as a radical discontinuity of personal life; immortality would follow Plato in seeing death as the separation of body and soul, a separation that actually liberates the soul from its imprisonment in the material body (Phaedo 64c). Hence, even in those Christian accounts, e.g., Aquinas, in which the soul does continue upon death, the separation of soul and body is not usually celebrated as a superior state. Quite to the contrary, the state is temporary, the soul’s knowledge is confused, and, most important, the person is incomplete (ST I.89.3; I.75.4 ad. 2). At the other end of the spectrum, others have held that the soul experiences death with the body or else may sleep until the general resurrection of all. And variations on these positions abound.

Recent Proposals: The Engagement with Neuroscience

Recent advances in neuroscience have been understood by some theologians and neuroscientists to eliminate the need to speak of soul.³ The general trend has been to avoid substance dualism generally attributed to the errors of Descartes, emphasize instead the person as a body-mind unity, and construct a theological account whose strong emphasis on the body can incorporate developments in neuroscience. Thus Nancey Murphy “denies the existence of a nonmaterial entity, the mind (or soul). . . .”⁴ Murphy, who calls her position “nonreductive physicalism,” believes that the human nervous system, operating in concert with the rest of the body in its environment, is the seat of consciousness (and also of human spiritual or religious capacities). Consciousness and religious awareness are emergent properties and they have top-down causal influence on the body⁵

Likewise, Philip Clayton, who calls his position “emergentist monism,” discards the traditional conception of the soul as an unnecessary encumbrance to the theological engagement of science.⁶ For both Murphy and Clayton, their differences notwithstanding, the issue turns on how the mental is to be construed, since they treat soul as the equivalent of mind. Both Murphy and Clayton are aware of other traditional understandings of soul, including its spiritual capabilities, but in order to engage neuroscience on its own terms, this third level of reality is a fortiori ruled out along with the mind. Murphy claims that “we are our bodies,” but she also wants to retain, as does Clayton, “ ‘higher’ capacities” of our humanity, including, “rationality, emotion, morality, free will, and most important, the capacity to be in relation with God.”⁷ Let us briefly consider some of the relevant neuroscience, question some salient points of this “soulless” trend, and then offer our own assessment.

Advances in neuroscience have progressively revealed that specific mental processes and behavior can sometimes be tightly linked to either a localized area of the brain or to systems or networks in the brain. For example, in 1848, Phineas Gage, a foreman for a railroad company laying rail in Vermont, was the victim of a freak accident. As a result of a premature explosion, a tamping iron shot through Gage’s left cheek at high speed en route to piercing his skull and the front of his brain before exiting and landing about 100 feet away. This iron bar was about three feet, seven inches long, one and a quarter inches in diameter, and weighed a little over thirteen pounds.⁸ Somehow, even though part of his brain had been destroyed, Gage survived and even remained conscious and rational. However, according to the reports of his attending physician, from that point forward, his previously reliable, efficient character, including his likes, dislikes, and morals, changed drastically. He became irreverent, given to gross profanity, and apparently incapable of remaining at any one job. In Antonio Damasio’s assessment of this case, even though most of Gage’s rational abilities were intact, “Gage was no longer Gage.”⁹ The damage to his brain evidently changed something quite basic about him.

More about the brain and its link to human behavior was discovered in 1861 when Paul Broca demonstrated a strict correlation between a lesion of the middle posterior part of the frontal lobe of the left hemisphere and speech loss (aphasia). Much later, with the advent of new technologies, such as brain imaging done by positron emission tomography (PET), functional magnetic resonance imaging (fMRI), and new developments in electroencephalography, the linkages have been drawn ever tighter. The new imaging technologies indicate differential distribution of electrical and chemical activities of cerebral regions that predictably vary with the psychology of the subject. Thus, according to French neuroscientist Jean-Pierre Changeux, from images of mental states, actual mental states can be inferred.¹⁰ Changeux conjectures that a PET scan of Theresa of Ávila’s brain taken during her mystical experiences could determine whether she was hallucinating or having epileptic fits. Similarly, he educes evidence to suggest that Blaise Pascal may have been experiencing symptoms of epilepsy during a mystical experience.¹¹ More recently, experiments have been done on cats and monkeys in which the corpus callosum (the fibers connecting the left and right hemispheres) is severed. These experiments, along with data from the small group of human patients who had similar procedures to alleviate severe epilepsy, indicate that the patient ends up with two centers of consciousness.¹² Additionally, in patients who have suffered a stroke and lose the ability to recognize faces, CT scans have been able to specify the damaged area. In consideration of such linkages between brain function and higher level behaviors, Murphy concludes that “nearly all of the human capacities or faculties once attributed to the soul are now seen to be functions of the brain.”¹³

But it is not clear why recent findings of neuroscience refute earlier understandings of the soul. After all, while Aquinas, for example, did not know of a certainty that the brain is the organ of thinking, he too posited a very tight linkage between soul and body. Does ignorance of specific brain functions refute a position that so strongly stresses the unity of soul and body? The scientific advances that have told us so much about how the brain functions would be unlikely to have troubled Aquinas. The ancients and medievals certainly knew that a blow to the head could cause someone to lose consciousness or to become “batty” in their behavior. Malcolm Jeeves, a neuroscientist well versed in theology, cautions that in neuroscience, the data “do not arrive with a label attached telling us what they all mean.”¹⁴

One possibility is that the data could lead to the belief that it is no longer possible to have a real relationship with a real God. This view, however, is not the position of Murphy and the nonreductive physicalists. Their position is that we can have a relationship with God, but we do not need an immaterial soul or even an immaterial mind to do so. Thus evaluating the data of localization studies that show a particular part or system of the brain involved in activities like “language, emotion, and decisionmaking,” Murphy tells us that “it is the brain that is responsible for these capacities, not some immaterial entity associated with the body.”¹⁵ Here the strangeness of the language used, “the brain . . . is responsible,” may betray a larger problem. Is the brain responsible for our higher capacities, or is it the essential (and remarkable) tool of those capacities? What is at stake here is whether there is anything immaterial in human consciousness.

Working in the 1930s, Canadian neuroscientist Wilder Penfield observed that while brain stimulation could force a patient to do certain things, the patient retained his freedom of belief, his will, typically responding, “I didn’t do that. You did.” Penfield concludes: “There is no place in the cerebral cortex where electrical stimulation will cause a patient to believe or decide.”¹⁶

Taking up the debate over neuroscience with Jean-Pierre Changeux, Paul Ricoeur questions whether scientific models can capture the richness of actual biological, lived experience, including spiritual experience. He allows that there is a causal link between neuronal dysfunction and the higher aspects of human behavior, but contends that things are quite different when the brain is functioning normally. Here “the underlying neuronal activity is silent in a way.”¹⁷ As we saw above in Chapter Two, lower level functions are typically necessary for higher level activities, but they are normally insufficient to explain those higher activities. The higher level can be perverted or destroyed altogether by lower level trauma, but given normal lower level functioning, what transpires on the higher levels cannot be explained in terms of lower level mechanics.

The silence of the properly functioning brain points to the seamless manner in which the unifying force of personality is our most basic identity. We never ask our brains to think; we just think. We do not normally ask our souls to detect and cherish the divine presence; we just do so. Neither from the silence of a well functioning brain, nor from the dramatic cases of brain malfunctioning should Murphy’s “ontological reductionism” be inferred.¹⁸ A brain is necessary for human consciousness, but it would be strange indeed to say that consciousness is in the brain.

“Nonreductive physicalism” and “emergentist monism” are intermediate positions. They represent attempts to carve out a position between “eliminative materialism” and “substance dualism.”¹⁹ However, in a passage cited by Clayton, Jaegwon Kim, one of the central figures in these debates, points out: “Nonreductive materialism is not a stable position. There are pressures of various sorts that push it either in the direction of an outright eliminativism or in the direction of an explicit form of dualism.”²⁰ If everything is explained in physical terms, there is clearly no need for a mind or soul (and the same would follow for God); hence, the force of eliminative physicalism. By contrast, in the intermediate positions, the reality of different “levels,” “properties,” “dimensions,” or “aspects” is being asserted, but any kind of mental or spiritual substance, that unwelcome inheritance attributed to Descartes, is denied.²¹ But if nonphysical realities are claimed to exist and to possess causal power (“top-down” causality, where the mental level can affect the brain level), isn’t the nose of the spiritual camel already under the flap of the physicalist tent?

Since no theologian could accept eliminative physicalism, the issue comes down to this: What reality do the believed-in higher levels have? As Kim suspects, does denying any ontology beyond the physical inevitably lead to a gravitational collapse upon physicality? Clayton perceives this danger and counters it, but as he does, the fragility of the intermediate position is again revealed. He really does two things. He insists on monism because “only one kind of thing exists,” i.e., the physical. But then he tells us that something new emerges from the physical that cannot be understood in terms of the physical:

We need multiple layers of explanatory accounts because the human person is a physical, biological, psychological, and (I believe also) spiritual reality, and because these aspects of its reality, though interdependent, are not mutually reducible. Call the existence of these multiple layers ontological pluralism, and my thesis becomes clear: ontological pluralism begets explanatory pluralism.²²

Pushing hard on this second component of his position, and explicitly rejecting “physicalism,” Clayton perspicaciously argues for an “ontological thesis,” namely, “that human persons, correctly and fully understood, include a spiritual dimension which, whatever else it is, is more than physical.”²³ Given these clearly stated ontological claims, does it still make sense to speak of “monism”?

The monistic claim is further called into question when we consider that, if God is Spirit (John 4:24), then there is at least one truly non-physical agent upon which all theology is based. As Clayton puts it, “theologians . . . are committed to the existence of a spiritual being or dimension which, while it may include the world, transcends it as well.”²⁴ But if we admit the spiritual ontology of both God and human persons into the discussion, monism no longer seems an adequate title for what is being claimed.

A common pattern is that almost all who enter this fray argue for different “levels,” “dimensions,” “aspects,” or “properties” while claiming to avoid dualism. Attempting to avoid prejudicing the discussion by a title, Jeeves suggests that we circumvent the terms “physicalism,” “mentalism,” “dualism,” and “monism.” Instead, he describes “the intimate relationship between brain and mind, or soul and body, as one of irreducible intrinsic interdependence and of duality without dualism.”²⁵

Whether monism or dualism is defended, my thesis is that two things will be present in every sensible discussion: some form of twoness and a way to unify the twoness. The higher level of the twoness can be called an “aspect,” “dimension,” “property,” or “level” of the more basic brain, or described as “duality without dualism.” And some theorists such as William Hasker expressly advocate dualism.²⁶ But in order to account for the range of human and divine activity, each account will have, under one title or another, some sort of twoness and some basic way to unify the twoness. And the most effective way to account for the overall unity is by some account of person that can be distinguished from nature alone.

Let us remember that what sparks the original entrance of “soul” language into the New Testament and the following Christian tradition is a concern for more than this life alone. Let us remove the “Cartesian” straw man and think instead about Paul, other New Testament writers, the Patristic leaders of the church, and Aquinas. These Christian writers do not endorse dualism, but rather, emphasize the connectedness of the soul to the body in this life, and insist on some form of embodiment in the next. In this light, is Jeeves, like many others, not essentially saying, “duality without dualism” is good twoness; dualism is bad twoness? Regardless of the terminology used to characterize a position, anyone who does not completely capitulate to materialism must assert the reality of the higher level. Once a higher level is asserted, one’s preferred label is of secondary importance. Whatever form of twoness is proposed is not the final word, because the twoness will be enveloped in a greater unity.

Since the hypostatic union settled upon at Chalcedon, in which the two natures of Christ were unified in one Person, Christian thought has consistently opposed dualism through the unifying force of the person. Just as the one Person unifies the two natures of Christ, so too are the different levels of body, mind, soul, and spirit unified in each human person.

The debate about neuroscience may display what Clayton insightfully calls a “fractal divide,” for it is the latest variation of an even older fractal divide — that between the allowance or rejection of transcendence in understanding the finite.²⁷ In the postmodern trajectory from Nietzsche to Derrida, we have seen how the a priori denial of transcendence governs their discourse and how the battle over the finite context becomes a proxy battle for the debate over the human person. The debate about neuroscience, fought over the central system in the human body, follows suit. While Murphy wants to retain anthropological unity, her attempt to do so by “ontological reductionism” parallels the postmodern denial of transcendence.²⁸ By eschewing the soul and stripping anthropology down to the brain, is there not an inconsistency between the physicalist ontology that remains and the higher goal of relationship with God?

A Stretched Ontology: The Emergence of the Soul

Because reasoned faith cannot be sustained if its referent does not exist, people of faith must be committed to multiple levels of being, i.e., at least two levels, for God is Spirit. Unfortunately, when the debate devolves to accommodating the concept of mind to advances in neuroscience, the ontology of spirit, whether of God’s or of the human soul, is too often missing from the discussion.²⁹ Is mind equivalent to soul without remainder?³⁰ From the New Testament to the present, soul has normally found its place in the context of an ontology that portrays the human being as the created partner of the God who is Spirit. The tight mind-body correlation that advocates of nonreductive physicalism propose could possibly account for such things as athletic accomplishment. But is a mind-body relationship sufficient to account for the highest exercise of human freedom in response to God?

Interestingly, Warren Brown, one of the advocates of nonreductive physicalism, describes something quite close to what I am arguing about the soul, but he does so while denying its ontology. As Brown puts it,

Despite the physicalist accounting we are attempting in this volume, it is difficult to avoid use of the word “soul” in this discussion as well. The word designates something within us that is at once both deep and transcendent. While arguing for a more embodied understanding of this aspect of our experience, the experience itself cannot be denied. Thus, “soul” (or at times “soulful” or “soulish”) is used herein to designate not an essence apart from the physical self, but the net sum of those encounters in which embodied humans relate to and commune with God (who is spirit) or with one another in a manner that reaches deeply into the essence of our creaturely, historical, and communal selves.³¹

When Brown writes of reaching “deeply into the essence” as a result of communing with God, when he tells us that “something within us . . . is . . . deep and transcendent,” and that its “experience itself cannot be denied,” he has, in spite of his protestations about remaining a physicalist, affirmed virtually everything non-physical at issue about the soul. However, he apparently would have us accept the non-physical descriptions without the non-physical actuality. His denial of “an essence apart from the physical self” is something of a straw man, for it is not clear that anyone actually holds that position.³²

Similarly, Joel Green, who sets out as the biblical defender of monism or nonreductive physicalism, ends up concluding, “Paul’s language is dualistic but in an eschatological, not an anthropological, sense.”³³ Green’s admission is significant, because “eschatological” dualism, i.e., anthropology reassessed in light of the resurrection, is precisely what prompted the early Christian conceptual development of the soul. Jesus’ resurrection and the hope for our own provoke a new kind of thinking about our own humanity, never one that is ultimately dualistic, but one that recognizes the ontological difference between God and humanity, for a full human life is one lived in ever greater openness to the ever present Spirit of God. As T. F. Torrance has pointed out, “The doctrine that in Jesus Christ God’s own eternal Logos had personally become man within space and time shattered all forms of cosmological dualism, whether Platonic, Aristotelian, or Stoic, which did not allow for any interaction of God with the empirical world.”³⁴ The unified view of the world and humanity in relation to God is quintessentially Christian. It does not require Murphy’s “ontological reductionism” to be accomplished. Instead, the Christian focus on person, both Christ’s and our own, functions to unify the inherent tension of different natures.

The Counterpart of the Spirit

The primary application of the term spirit is always to God, who is infinitely actual and active Spirit. Being made in the image and likeness of God, the human spirit, the higher aspect of the soul, comes alive only as it ceases to resist cooperation with God. Sin has many meanings and forms, but its primary one is to deny the gift of relationship with God. Relationship with God is never static, and all those who enter into this relationship in faith cannot but be changed, not just once, but in every event in which this relationship occurs. In Irenaeus’ second-century account, something happens when we receive the Spirit — the soul undergoes a process of sanctification; likewise, something happens when we refuse the Spirit — we remain in animal, carnal nature and thereby fail in the appointed essence of our humanity — to become ever more than we currently are.³⁵ Capturing this sense of process and movement in the relationship with God, Brian Daley comments upon Gregory of Nyssa’s understanding of soul: “Perfection . . . is a never-ending process of growth towards God, an endless growth in the human subject’s reflection of, and participation in, God’s infinite qualities of goodness and beauty.”³⁶

The import of this early Christian understanding is not adherence to a dualism of substances, since these thinkers emphasized the unity of the human person just as they came to emphasize the unity of Christ’s one Person in two natures. Rather, the import is that the relationship to God initiates a stretched ontology, where the human partner is always becoming something more than in the leading edge of its being, that is, in its soul. The spiritual dimension of the soul emerges because of the relationship to God, and thus cannot possibly be understood in terms of neurobiology, even though the emergence will not take place apart from neurobiological functioning. Unlike the veritable dualism of the Gnostics, the importance of the body has always been integral in orthodox Christian doctrine. The unique opportunity of human personhood is that the spiritual soul can be evolved in a historical, mostly material being, not by withdrawing from the world, but by properly engaging