Wednesday, March 11, 2009

Neuroscience and the soul.

A recent letter from Martha Farah to Science Magazine is worth passing on:
Science and religion have had a long relationship, by turns collegial and adversarial. In the 17th century Galileo ran afoul of the Church's geocentrism, and in the 19th century Darwin challenged the biblical account of creation. The breaches that open at such times often close again, as religions determine that the doctrine in question is not an essential part of faith. This is precisely what happened with geocentrism and, outside of certain American fundamentalist Christian sects, evolution.

A new challenge to the science-religion relationship is currently at hand. We hope that, with careful consideration by scientists and theologians, it will not become the latest front in what some have called the "culture war" between science and religion. The challenge comes from neuroscience and concerns our understanding of human nature.

Most religions endorse the idea of a soul (or spirit) that is distinct from the physical body. Yet as neuroscience advances, it increasingly seems that all aspects of a person can be explained by the functioning of a material system. This first became clear in the realms of motor control and perception. Yet, models of perceptual and motor capacities such as color vision and gait do not directly threaten the idea of the soul. You can still believe in what Gilbert Ryle called "the ghost in the machine" and simply conclude that color vision and gait are features of the machine rather than the ghost.

However, as neuroscience begins to reveal the mechanisms underlying personality, love, morality, and spirituality, the idea of a ghost in the machine becomes strained. Brain imaging indicates that all of these traits have physical correlates in brain function. Furthermore, pharmacologic influences on these traits, as well as the effects of localized stimulation or damage, demonstrate that the brain processes in question are not mere correlates but are the physical bases of these central aspects of our personhood. If these aspects of the person are all features of the machine, why have a ghost at all?

By raising questions like this, it seems likely that neuroscience will pose a far more fundamental challenge than evolutionary biology to many religions. Predictably, then, some theologians and even neuroscientists are resisting the implications of modern cognitive and affective neuroscience. "Nonmaterialist neuroscience" has joined "intelligent design" as an alternative interpretation of scientific data. This work is counterproductive, however, in that it ignores what most scholars of the Hebrew and Christian scriptures now understand about biblical views of human nature. These views were physicalist, and body-soul dualism entered Christian thought around a century after Jesus' day.

To be sure, dualism is intuitively compelling. Yet science often requires us to reject otherwise plausible beliefs in the face of evidence to the contrary. A full understanding of why Earth orbits the Sun (as a consequence of the way the solar system was formed) took another century after Galileo's time to develop. It may take even longer to understand why certain material systems give rise to consciousness. In the meantime, just as Galileo's view of Earth in the heavens did not render our world any less precious or beautiful, neither does the physicalism of neuroscience detract from the value or meaning of human life.


  1. Somehow in our time, we've come to equate noun functions with substance without sensing substance in verb functions. 'Soul' exemplifies this idea. No one really knows what a soul as noun is, but we all recognize when something is being soulful- the verbal state.

    Look at your hand. Is it more accurate to notice it as a noun or a verb? Isn't your hand really a handing? What I mean is that the hand really consists of an order in constant movement that keeps your hand intact as your hand. Even when you hold your hand flat and still, it remains abustle in constant movement without disintegrating.

    Soul, when we understand it's substance as being constituted by verb functions, speaks to dimensions where we experience signals with depth and meaning, not as mere stimulants. Soul may not be a thing, but we crave its phenomenon.

  2. In complement to the very Wittgensteinian way Gottschalk handles the question, a different problem built into this conclusion. It seems that until neuroscience determines what exactly it is about recursive, self-organizing, complex systems that allows these correlated brain states to become “what it is like to be” the organism or individual in question, it will have a very difficult time supplanting the soul. The soul seems to come from objective observation of our subjective, first-person perspective and the difference between what information observation reveals and what we experience. Any theory of consciousness should handle this difference as well as explain the qualitive aspects of experience.

    “It may take even longer to understand why certain material systems give rise to consciousness.” This is a laudable goal for neuroscience. However, it remains to be seen whether or not consciousness comes under the purview of this particular discipline. It may be that the brain is not a recursive, self-organizing system, but this seems to be the case. If it is the case, then the recursive nature of the system means that the first-person, subjective experience has a causal role, which may extend beyond or at least influence the physical states of the brain, forcing causation in the brain to be more along the lines of a limited probability. Unless we find a way to objectively observe subjective experience, this area of study will be partially hidden to us. While hidden, the subjective experience could keep us from an adequate explanation of consciousness.

    As for the soul, it is a positive metaphysical claim and as such requires supporting evidence beyond our inclination to dualism. There is no such evidence, and until we come across some, we should set the concept aside (to the realm of mystics and dreamers).

  3. Nathaniel, this would be a great conversation in a pub. Though I'm not a practicing scientist, I seek to understand consciousness with the same rigor that you do. In no way do I want to supplant scientific understanding; I do hope to add to our overall understanding though. Let me begin.

    As a young man, I spent a summer repairing and tuning collectable Ferarri's. The onus was mine to understand mechanics and dynamics in general, and make them specific to the car under my care. The best part of the job was that I got to drive Ferarri's at speed around race tracks: I know in a most sensual way, the difference between driving the car, and understanding its underlying mechanics. Driving and mechanics are separate domains.

    This illustrates the paradox of human subjectivity: Imagine that one day you find the underlying mechanical structures that give rise to recursivity. From this, you develop the technology to build a suit that by wearing it, allows the user to turn various knobs in order to modify those underlying mechanics, thereby giving him the ability to truly adjust his subjectivity- by scientific standards.

    You're the Edison in this, so you're the first one to try it out. Imagine- the final snap is snapped. You shruggle a bit to get the suit to loosen up around your crotch, and you note the first design modification.
    Watson, aflutter with anticipation, writes it down. A final check- every thing's in order; you touch the first switch and pause: you make for yourself a moment. In this moment you ponder the outcomes of flipping the switch.

    The pregnant moment- pregnant with subjectivity waiting to be born. A moment filled with something vital that, such a suit as "yours" aborts.
    This moment, when I contemplate its profundity, drives me to awe.

    This moment, regardless of it origin, exists as another domain; I don't need the suit, because this elegant genius in which we already participate -what I have referred to as soul- makes the suit look crude and stupid in comparison.

    Soul, as you say, is a concept belonging to mystics and dreamers; I agree if that's the name for one who loves and understands the phenomenon of the 'moment'. Your 'suit' not only feels like a bad dream, it amounts to something like training wheels for the genius we might call soul.

    Nathaniel, driving is another domain....

  4. In a perfect world Nathaniel, we would indeed be carrying out this dialogue over a couple of beers. And hopefully, I've convinced you that 'soul' is something beyond scientific inquiry where it is something beyond recursivity: Soul embodies our experience of depth. Having settled this, we would then talk about all the underlying 'mechanics of our Ferarri's' and soulfully look in awe at such fine 'machinery'.

  5. As a tutor, I have had to help a great many people this last week for midterms and have not really had time to form a cogent response. Gottschalk, you construct very vivid and powerful metaphors you put a good deal of thought into your words. The main weakness in using metaphor is determining the exact extent to which the imagery relates to the subject at hand. It is clear that the car represents the physical body. The form and function are similar enough to make it work. A question remains about weather driving relates strongly enough to the soul.

    I believe we can agree that the primary components of the soul include identity (it carries the meaning of self), Intentionality (it expresses will on the physical world), phenomenal experience (what it is like to experience an event), an aspect of supernatural (it does not exist in the observable world), and permanence (the continuity of experience that, in this case, can continue without the body). Driving as a metaphor only expresses intentionality and phenomenal experience. Identity is already bound up in the concept of driver, which is distinct from driving itself. While it is an exhilarating experience to drive such cars, I think it is safe to say that it is not supernatural. As far as permanence is concerned, it would be difficult to drive without the car.

    If we are referring to intentionality and phenomenal experience, the existence of each is possible without the concept of the soul. For a greater part of Christian history, animals were not considered to have souls, but no one denied them intentionality (they control their own movements). It is obvious that there is something it is like to be a bat, but I doubt it as universally accepted that they have souls. Only the supernatural component and permanence (beyond the physical) require what we consider the soul. Because each of these is bound up in the definition of the soul, it remains to be proven that they exist at all. If we claim that identity, intentionality or phenomenal experience are beyond the bounds of observable reality, we must make that claim without the existence of the soul because they are not contingent. Only the supernatural elements of the soul exist beyond observable reality by definition; everything else must be proven to exist beyond physical description.

    The problem with determining what science can and cannot observe is that this is a moving target. We see what scientific inquiry can prove today, and we wish to extrapolate it to what science will be able to see in the future. The last hundred years or so have proven that we will have no idea what science will and will not be able to determine. That is why when I denied that subjective experience is within the realm of neuroscience, I withheld judgment as to whether or not it could in time it could explain the phenomenal. I simply outlined what it would mean for science to do so.

    Many in dealing with this kind of issue believe that because science cannot directly observe something that event is beyond the purview of science. However, when we look at things like black holes we see that science can deal with an event of which they have no direct observation. The soul must interact with the physical in some way in order to have any real intentionality. This interaction could lead us to a way to observe indirectly the mechanisms of the soul. We could gain a great deal of knowledge even if we lack the tools necessary to get its height, weight, or mass.

    This is all that I have time for now, but I have some questions about the “subjectivity suit” thought experiment, so to be continued.

  6. Nathaniel, I so appreciate your thoughts and engagement. I only have a moment right now but I at least want to acknowledge your good thoughts. I too will be back to read your work; not to find holes, but to consider and learn.

  7. Good morning Nathaniel, (Sun. march 22)

    If I'm reading your thoughts rightly, it seems that you are seeing my use of the word soul in its arcane context of 'the ghost in the machine'. Actually, I'm not doing this at all; I'm not saying that science can't or shouldn't find the "soul" as you seem to be conceiving it. Instead, I'm pointing out a paradox represented by the "subjectivity suit": If we assign the number 0 to a situation devoid of subjectivity and then assign a numerical value to all of the determining processes underlying consciousness, we'll end up with an infinitesimal numerical solution of .999..., as long as human being can experience the subjective moment described in the word, consider.

    I'm enlisting this classic word, soul, because I think it aptly carries a uniquely human dynamic: we can create a "now" in time's constant march of past into future; while carried along by the power of this universal stream of reality, human being is the one who can plant their feet into the stream's bottom and feel the water's momentum part around their legs.

    Soul as a concept has no explaining power; its power arises from its descriptive abilities. We may never know what a "soul" is, but we know it when our experience feels soul-full. A soulful experience is one that opens up the dimension of depth to us: here is where meaning transcends lexography. Since no one can prescribe what is meaningful to you Nathaniel-or anyone else for that matter- soul is beyond science's ultimate grasp. Soul is its own domain needing its own particular methods and 'tools'. One of them being dialogue such as ours.

    I think that by giving soul the purchase of the concepts domain or dimension which arise from physical processes, but doesn't equate to them, we could talk more intelligently about something that is perhaps the most salient feature of being human: experiencing life in its dimensions of depths.

    Sometimes in science, we conflate explanation with description: we can describe energy, matter and the relationship of speed/time to change, with great prowess- but no one can explain these things themselves. If we could explain them, we'd then be able to make energy and matter. But we can't; we can only transform them- the science of thermodynamics is built from this fact.

    A key feature of dimensions is that they can intersect one another. Soul as a dimension feels apt to me. Certainly- all of the underlying physical processes affect our dimension of soul: in a situation where I shared a dialogue with a man who conceived his struggle in terms of an anger problem, I explained the role of the amygdila (thank you neuroscience); his anger problem became a fear problem. He then engaged his soul differently.

    I'm curious Nathaniel, what are you studying and tutoring in?

  8. Anonymous4:55 PM

    I agree with you. A good book to read that analyzes the bible and neuroscience on the body-mind problem is John Cooper's "Body, Soul, and Life Everlasting: Biblical Anthropology and the Monism-Dualism Debate."

  9. Interesting conversation. I think I agree in large part with Nathaniel.

    I have a number of questions about the mind/body debate, neuroscience and subjective experience.

    Most reasonable people will agree that our subjective phenomenal experience is a real thing, and constitutes part of reality. As such, it then requires an explanation if our curiosity is to be satisfied. The dominant modern view is materialism, that is that all parts of reality can be explained by physical stuff and their interactions.

    However, I am unsure whether subjective phenomenal experience is actually amenable to materialism and the scientific process.

    The scientific process is the best method we have developed to find the objective truth about reality. As Nathaniel pointed out though, science operates by abstracting away the specific and the subjective, in order to get at the general and objective (different people repeat the same experiment, we attack the same problem from multiple angles and perspectives - all this gets correlated to remove specific circumstances and subjective interpretations and get at the underlying principles).

    But how does this apply when the target IS subjective experience itself? Wouldn't science then be abstracting away the very thing we are trying to explain?

    What are the limits of science itself? As a formal system, the scientific process must have limits (as demonstrated by the likes of Godel and Turing). Subjective experience is one of the building blocks on which the scientific method is based (i.e. multiple observations of the same phenomena by different observers - what remains the same?) as such is it even possible to explain it scientifically? Note here that I am not talking about the limits of science in terms of the "God of the Gaps" - stuff that science hasn't explained, but in terms of the limits of the process itself - what science can ever possibly explain (i.e there may be lots of things science hasn't yet explained, but still remain within the realm of things science can explain).

    Another issue is what constitutes an "explanation". We generally explain things two ways, by reduction and by analogy. We accept as good explanations those that provide us with a degree of predictive ability. So for example, we explain chemical reactions by reducing them to their molecular components, and we accept this explanation because molecular algebra allows us to predict various chemical reactions.

    BUT nothing we know about information and neuronal processes predicts the existence of phenomenal subjective experience.

    We can use such knowledge to accurately predict certain behaviours, and we can replicate brain information processes (such as retinal image processing) on computers and get the same results as the brain. Yet we still have not the slightest clue on how subjective experience arises. There's nothing in our descriptions of information processing in the brain that allows us to derive phenomenal consciousness.

    We have plenty of correlational data. However, that is only one part of an explanation. We still need the connecting algebra that allows to make novel predictions about brain state/subjective experience relations that we haven't observed as part of our data (i.e. brain state A + brain state B = subjective experience C). We need a constructivist explanation that shows HOW brain states A and B result in subjective experience C.

    If we accept that phenomenal consciousness is a part of reality, but nothing we know about information and brain processing requires, predicts or can derive it, and it is beyond the realm of
    things addressable by the scientific method, what are we left with?

  10. My take on this is to pass on the abstracting of Metzinger's positions, which I put in my Istanbul talk (see left column of mindblog):

    What he calls the Ego Tunnel (or PSM) is a complex property of the global neural correlate of consciousness (NCC) - what make “Mineness” or “I” possible - a vastly reduced model of what is really 'out there'

    - It is a transparent mental image that allows the conscious experience of being a self to emerge. (Transparency is our not seeing seeing the firing of neurons in our brain, only what they represent for us).

    - The model at a given moment is transparent because the brain has no chance of discovering that is is a model - it is a higher order representation integrating its information in longer time window than the lower order information processing in smaller time windows. Our visual perception time window is much larger than the time windows of primary visual processing and so those more rapid underlying processes are completely invisible to it (the same thing as not being able to see the individual frames in a movie reel, because our visual integration time is much longer). It is a metabolically efficient, quick and dirty way of knowing only what our evolution has deemed it necessary for us to know.

    - Our ancestors did not need to know that a bear-representation was currently active in their brains or that they were currently attending to an internal state representing a slowly approaching wolf....All they needed to know was “Bear over there!” or “Wolf approaching from the left!”

    -In this view, Consciousness is taken to be the space of attentional agency, that set of information currently active in our brains to which we can deliberately direct our high level attention. Low level attention is automatic and can be triggered by entirely unconscious events.

    -A further assertion is that consciousness is epistemologically irreducible... one reality, one kind of fact, but two kinds of knowledge: first-person knowledge and third-person knowledge, that never can be conflated.

    -There is a long list of ideas on why consciousness evolved, what it is good for, doing goal hierarchies and long-terms plans, enhancement of social coordination, etc.

    I like Metzinger's description of consciousness as a as a new kind of virtual organ - unlike the permanent hardware of the liver, kidney, or heart it is always present. Virtual organs form for a certain time when needed (like desire, courage, anger, an immune response)...they are a new computational strategy, that makes classes of facts globally available and allows attending, flexible reacting, within context.....

    ‘Reality generation’ allowed animals to represent explicitly the fact that something is actually the case, the world is present. (conscious color gives information about nutritional value, red berries among green leaves, empathy gives information about the emotional state of conspecifics).

    Old things in the evolution of consciousness are ultrafast and reliable (like qualities of sensory experience) and transparent. They are evolved hardware (as are our autonomic and neuroendocrine emotional chemistries) that support the new classes of transient virtual organs. Abstract conscious thought is not transparent or fast, it is slow and unreliable, experienced as ‘made.’

    Only our species has evolved advanced additional abilities to run offline simulations in the mind, experiencing some things are ‘real’ and other elements of our tunnel as mere thoughts about the world, representing that we are representational systems.