Particle or Wave? Human Nature as Both Physical and Mental

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There is an apparent conundrum in our understanding of human nature. The problem we encounter is how we should understand our physical brain/body functioning in a way that credits the reality of the subjective experiences of our minds. The thoughts, beliefs, decisions, emotions, and spiritual experiences that constitute our minds seem to be something very different from our bodily functioning. Thus, our subjectivity can seem to be at odds with a scientific neurophysiological account of ourselves.

One possibility is that these are indeed two separate categories of things: a physical body and a non-physical mind. Within conversations about Christian faith, we might refer to a body and a soul, rather than body and mind. This idea that we are made up of two separate parts is referred to as dualism, and for centuries it has been, in most cases, the default perspective in Christian understandings of the person.

However, modern neuroscience makes it hard to maintain the view that our minds are not a property of the physical functioning of our bodies, particularly our brains. Increasingly, neuroscience—as well as clinical neurology—paints a detailed and fine-grain picture of the neurophysiological basis of most every aspect of our minds.

As one of a multitude of examples, my students and I study individuals with a congenital brain abnormality. One core outcome of this condition is a diminished capacity for imagination and mental elaboration evident in a wide variety of situations and tasks. So, are our imaginations nothing but certain patterns of neuronal activity in our cerebral cortex? Or perhaps manifestations of a non-physiological, non-material separate part of us? It seems to be a conundrum.

In quantum physics there is a phenomenon called “wave-particle duality” which refers to the fact that an element of light (a photon) seems to be either a particle or a wave depending on the nature of the observation being made. The question arises: Is the basic constituent of light a particle or a wave? The answer is “both”!
Physicist and Anglican priest John Polkinghorne has suggested this phenomenon of quantum physics as an apt metaphor for thinking about the relationship between a mind and a brain. A single thing has two aspects, depending on how you encounter it. Encountered as a physical object, it is a brain/body. Encountered in the world of the mental, both subjective and interpersonal (thinking, feeling, believing, interacting with other minds), this same object—the brain/body—has different properties and must be described in a very different way.

The brain is a hypercomplex system with something like 100 billion neurons and 100 trillion synaptic interconnections, allowing for an astronomical number of possible functional states. What is more, it is becoming increasingly clear that in order to understand the mind, one must also consider the system that includes the body. This is due to the very tight, ongoing, reciprocal interactions between brain and body—as well as the intensive, moment-to-moment interactions with the social and physical context within which the particular brain/body is functioning. The brain/body is the most complex thing in the entire physical world.

Complex, interactive systems (even those with much less complexity than a brain/body) have been shown to have emergent action-properties, the causes of which cannot be attributed to the parts of the system but rather to the functional interactivity of the parts. Thus, the function of an automobile engine in driving the axel and wheels cannot be attributed to any particular parts, but to their organization and interactions within the whole of the engine. Similarly, our hypercomplex physical selves (brain-body-context systems) manifest phenomena (like thinking, feeling, believing, interacting with other persons, etc.) that cannot be attributed to the properties of neurons themselves, but emerge from their rapidly fluctuating patterns of interactivity.

In the end, we, as hypercomplex systems, demand two levels of descriptive language: one level that can account for our physiological functioning, and a second level that describes the higher level properties of the system that emerge from the mind-bogglingly numerous states of interactivity of the brain/body that constitute our mental lives. While only one thing exists, we encounter the thing in two seemingly different descriptive contexts, like light in both particles and waves.

Considering what is true within the domain of quantum physics and then considering what we know about the sorts of higher level phenomena that can emerge in the interactivity of complex systems, it seems that there is no necessary conflict between our scientific descriptions of human beings and the account of humankind presumed by Christian faith and descriptions of the subjective experiences of ourselves. We are one sort of being that can be correctly and truly described as both physical and mental, depending on how you choose to observe.

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Warren S. Brown is professor of psychology and has been at Fuller since 1982. He previously served as director of the Travis Research Institute. Dr. Brown has authored, co-authored, or edited numerous scholarly articles, book chapters, and books, including his most recent, Enhancing Christian Life: How Extended Cognition

There is an apparent conundrum in our understanding of human nature. The problem we encounter is how we should understand our physical brain/body functioning in a way that credits the reality of the subjective experiences of our minds. The thoughts, beliefs, decisions, emotions, and spiritual experiences that constitute our minds seem to be something very different from our bodily functioning. Thus, our subjectivity can seem to be at odds with a scientific neurophysiological account of ourselves.

One possibility is that these are indeed two separate categories of things: a physical body and a non-physical mind. Within conversations about Christian faith, we might refer to a body and a soul, rather than body and mind. This idea that we are made up of two separate parts is referred to as dualism, and for centuries it has been, in most cases, the default perspective in Christian understandings of the person.

However, modern neuroscience makes it hard to maintain the view that our minds are not a property of the physical functioning of our bodies, particularly our brains. Increasingly, neuroscience—as well as clinical neurology—paints a detailed and fine-grain picture of the neurophysiological basis of most every aspect of our minds.

As one of a multitude of examples, my students and I study individuals with a congenital brain abnormality. One core outcome of this condition is a diminished capacity for imagination and mental elaboration evident in a wide variety of situations and tasks. So, are our imaginations nothing but certain patterns of neuronal activity in our cerebral cortex? Or perhaps manifestations of a non-physiological, non-material separate part of us? It seems to be a conundrum.

In quantum physics there is a phenomenon called “wave-particle duality” which refers to the fact that an element of light (a photon) seems to be either a particle or a wave depending on the nature of the observation being made. The question arises: Is the basic constituent of light a particle or a wave? The answer is “both”!
Physicist and Anglican priest John Polkinghorne has suggested this phenomenon of quantum physics as an apt metaphor for thinking about the relationship between a mind and a brain. A single thing has two aspects, depending on how you encounter it. Encountered as a physical object, it is a brain/body. Encountered in the world of the mental, both subjective and interpersonal (thinking, feeling, believing, interacting with other minds), this same object—the brain/body—has different properties and must be described in a very different way.

The brain is a hypercomplex system with something like 100 billion neurons and 100 trillion synaptic interconnections, allowing for an astronomical number of possible functional states. What is more, it is becoming increasingly clear that in order to understand the mind, one must also consider the system that includes the body. This is due to the very tight, ongoing, reciprocal interactions between brain and body—as well as the intensive, moment-to-moment interactions with the social and physical context within which the particular brain/body is functioning. The brain/body is the most complex thing in the entire physical world.

Complex, interactive systems (even those with much less complexity than a brain/body) have been shown to have emergent action-properties, the causes of which cannot be attributed to the parts of the system but rather to the functional interactivity of the parts. Thus, the function of an automobile engine in driving the axel and wheels cannot be attributed to any particular parts, but to their organization and interactions within the whole of the engine. Similarly, our hypercomplex physical selves (brain-body-context systems) manifest phenomena (like thinking, feeling, believing, interacting with other persons, etc.) that cannot be attributed to the properties of neurons themselves, but emerge from their rapidly fluctuating patterns of interactivity.

In the end, we, as hypercomplex systems, demand two levels of descriptive language: one level that can account for our physiological functioning, and a second level that describes the higher level properties of the system that emerge from the mind-bogglingly numerous states of interactivity of the brain/body that constitute our mental lives. While only one thing exists, we encounter the thing in two seemingly different descriptive contexts, like light in both particles and waves.

Considering what is true within the domain of quantum physics and then considering what we know about the sorts of higher level phenomena that can emerge in the interactivity of complex systems, it seems that there is no necessary conflict between our scientific descriptions of human beings and the account of humankind presumed by Christian faith and descriptions of the subjective experiences of ourselves. We are one sort of being that can be correctly and truly described as both physical and mental, depending on how you choose to observe.

Written By

Warren S. Brown is professor of psychology and has been at Fuller since 1982. He previously served as director of the Travis Research Institute. Dr. Brown has authored, co-authored, or edited numerous scholarly articles, book chapters, and books, including his most recent, Enhancing Christian Life: How Extended Cognition

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