Dualism has supposedly fallen out of favor in modern science. However, a new form of dualism has taken root in recent decades that bears striking resemblance to long disavowed theories of mind. In this first of three parts, we will very briefly explore dualism's origin.
To understand the current ways in which the brain is thought about by the neuroscientific community, and, by extension, the popular imagination, we need to appreciate some historical context. It is necessary, therefore, to back up quite far in the history of philosophy and biology, way back, in fact, all the way to Ancient Greece and the writings of Aristotle. He wrote that each extant thing is comprised of two conceptually distinct constructs, “matter” and “form”. These concepts, while distinct, are at the same time inextricably linked in Aristotle’s view of the universe, with his meanings of matter and form being, very simplistically stated, an object and its “essence”, respectively, each “thing” being simultaneously an extant body and abstraction, neither having hegemony over the other. One of his famous illustrative examples is that an axe is comprised of a wood handle and iron head, which is the matter, and it also possesses the ability to chop wood, its form. Previously, Plato proposed that objects existed in the abstract, that there was a perfect object that existed a priori in the ideal, but that the ideal was not attainable on Earth. Aristotle rejected this view, favoring his matter/form dichotomy. Each thing has both matter and form, although they are not necessarily immutable, as matter can change shape, and therefore the form may be altered as well, as one could, say, melt the axe head to make some other iron tool.
Applying this concept to biology, Aristotle called an organism’s form its psuchē. The word psuchē has been translated from Greek as ‘soul’, but our concept of soul is not anything like what Aristotle meant. To him, psuchē was the essence of being. It is what is responsible for growth, reproduction, and, in the case of humans, for cogitation and cognition. Every organism has a psuchē in his view, be it a philosopher or a weed growing through the cracks of a sidewalk. Importantly, there was no reference to religion or religiosity in his conception of psuchē.
Developing this concept further, he hypothesized that each of us has a life force running through our blood vessels (pneuma) that allows us everything from muscle contraction to sensory perception. Even though Aristotle thought, ultimately, that the center of thought lay not in the brain, but rather, in the heart, his writings about the flow of the life force throughout the organism led eventually to the hypothesis that the ventricles of the brain were the seat of mental function, a position whose foundation was laid by Galen in the 2nd c. and elaborated on by Nemesius in the late 4th or early 5th c. The ventricles are a series of interconnected cavities in the brain throughout which cerebrospinal fluid (CSF) flows. That this constant flow was what was ultimately responsible for our mental abilities seemed a reasonable conjecture, because flow requires energy. (This is especially poignant in light of the accepted theory of motion of the time, also Aristotle’s, that an object’s natural state was rest.) The energy imparted to the CSF, which seemed to come from somewhere magical (bear in mind, while the blood is pumped by the heart, no such organ exists to pump CSF--that job is accomplished by cilia that line the ventricles, but of course these men lacked microscopes to aid them), is perhaps what gives rise to our mental powers, where the life force lay.
Aristotle’s construction of soul was very forward thinking, and perhaps far ahead of his time. The unbreakable link he places on matter and form, body and soul, could conceivably even strike one as a precursor to a materialist worldview, although certainly Aristotle believed in the divine. Nominally speaking, materialism is the dominant worldview of the broad science community, but, as I shall show in the following parts of this column, there are still many covert dualists operating in science. More on that in a bit.
The main conceptual problem that troubled the ancients and continues to haunt us in modern times, the reason that the concept of a life force was needed to being with, is that each effect has a chain of causality, but thoughts seem to break this chain. What causes a thought, especially a seemingly original or whimsical one? Thoughts appear to be void of a physical cause. This problem was “solved” by Descartes in the 17th c. Obviously, Descartes was a polymath whose contributions to the modern world are enumerable, but many, though by no means all (for example he was the first person to speculate about inhibitory inputs to the nervous system), of his contributions to neuroscience were, flatly, incorrect.
In his Treatise on Man Descartes conceived of two very separate entities that comprise the person. First, there is the body. The body is the material part of the person and encompasses that part of the nervous system responsible for reflexes and involuntary movements (e.g. one’s heartbeat). Second, there is the “mind”, or what we may consider the immortal soul. In Descartes model of the person, the mind controlled all aspects of cognition and cogitation, and was also responsible for directing voluntary muscle movements. Unlike Aristotle’s concept of the relationship between form and matter, here, the mind holds hegemony over the body. Furthermore, Descartes even proposed how the two entities are connected, namely, the mind gains access to the body via a connection with a small brain structure known as the pineal gland. Upon death, the mind/soul separates from the body and enjoys eternal life. It is undying unlike the body, which is only a temporary vessel for our time on Earth. To Aristotle the soul was incorporeal because it was an abstraction, and thus didn’t “die” because it couldn’t; to Descartes the soul was incorporeal, but was a thing itself that didn’t die because it was immortal. This is a non-trivial conceptual difference.
Descartes argued that humans are the only creature with a mind (soul), and they are, therefore, the only organisms that can be described as conscious (although, curiously, all mammals have a pineal gland, I believe). With his view that mind and body are separate as well as separable, Descartes offers a solution as to how animals can act like humans act in some circumstances, via their reflexes and involuntary movements, while preserving a unique and higher position for humans, that of a conscious being. Importantly, this is one of the earliest times that humans or animals had been described purely mechanically, and Descartes thus helped found the field that became known as physiology.
This bifurcated view of humanity has become known as “dualism”, and scientists generally regard dualism as unscientific and more in the realm of religiosity than of empirical inquiry. Hard numbers about how the neuroscience community views dualism are difficult to find, but anecdotally, one can say with confidence that there is not much support, nominally anyway, for a dualistic conception of man. One survey found that only 36% of individuals who identified as “medical professionals” support the idea that we have a soul that is separate from our bodies [1], compared with a much higher number among the general population. One would have to imagine that if just brain scientists were surveyed, the number would likely be much, much lower.
Despite this, it has been suggested by some thinkers that a nouveau form of dualism has emerged out of modern neuroscience. Part of the problem with Descartes’ theory, and a problem which he identified himself, was that if it truly isn’t your eyes that are seeing, as is definitely the case if his mind/soul is what is actually conscious, but rather that the image that falls on your retina is reconstituted on your pineal gland so that your soul can perceive the image presented to it, then this automatically begs the question of who is seeing for your soul? Doesn’t your soul then need its own eyes and pineal gland inside of it? The cycle is never ending unless we permit the soul to be purely supernatural, which Descartes appears to have done; but, surprisingly, this is almost completely analogous to the language of modern neuroscience. Let’s examine this passage from Kurzweil, for example.
- Consider a situation in which someone performs an action with no awareness that she is doing it—it is carried out entirely by nonconscious activity in that person’s brain. Would we regard this to be a display of free will? Most people would answer no [2].
Is this any different from Descartes? Kurzweil firstly regards an activity as being carried out in a person’s brain.This begs the same question that if a brain thinks for the person, who thinks for the brain? This time we can’t summon magic as Descartes may have done. Cognition and cogitation are functions of man, not of our brains: This is the thrust of our misconception. Secondly, he regards unconscious activity as being purely mechanical, with the converse presumably being that conscious activity may have a component of free will. Replace “brain” with “mind” and we have classical dualism. I have chosen Kurzweil’s recent popular publication to pick on because this type of vernacular has seeped into the popular consciousness from the academic literature. The fact that it is in popular science shows how pervasive it has become, as popular writers take their cues from their scientific counter parts. In the next installment, we will address neodualismin academic neuroscience writings from such giants of the field as Kandel, Gazzaniga, and Crick, and I shall show that the brain has become the new mind/soul.
1. Demertzi, A., et al., Dualism persists in the science of mind. Ann N Y Acad Sci, 2009. 1157: p. 1-9.
2. Kurzweil, R., How to create a mind : the secret of human thought revealed2012, New York: Viking. 336 p.
Another great post. IMO the root of this dualism is not only pervasive in neuroscience, but also in physics, astronomy, and evolutionary biology. In the simplest terms, I believe it is the ultimate reluctance to consider ourselves in position that is not unbiased by our awareness. Even efforts to consider ourselves from a perspective of experimental fact, are usually presented as lessons in humility or exercises in uncommon thinking, rather than a foundation on which to build a consistent model that includes ourselves and everything else.Cognition and cogitation are functions of man, not of our brains: This is the thrust of our misconception.
Yes, we agree. I was reiterating was I thought you were saying, not contradicting. Our form of consciousness gives us a perspective on the universe that we can't divorce ourselves from. Its an intractable problem. I had a theoretical physics prof in grad school (incidentally, the smartest person I've personally ever met) who used to always talk about how man had never come up with a purely abstract mathematics. That is, every mathematics system we have created has eventually found an application in physics. He believed this was a result of our type of consciousness, that we're part of the universe and can't imagine anything that isn't.
That is awesome. I think we need a paradigm shift for consciouness akin to Special Relativity. Just go where the reproducible experiments lead, and bring nothing else.That is, every mathematics system we have created has eventually found an application in physics. He believed this was a result of our type of consciousness, that we're part of the universe and can't imagine anything that isn't.
A very strong summary of dualism, I wouldn't have necessarily considered Greek thinkers as a forefront of dualism but instead started at Descartes, so it's an interesting perspective. Aristotle's Psuche was considered to have separate levels for humans and plants depending on their purposes, such as breathing, conscious thought and movement. Anyone reading Aristotle's De Anima (On the Soul) should remember that Psuche and Soul are pretty much analogous to some translators, even if our modern conception of the soul (Which is fairly bastardized), is very different.
You can even have Psuche for objects that aren't alive; the psuche of an axe for example would be 'to cut', or the psuche of the eye would be 'to see'. Aristotle comes to the same kind of conclusions than Descartes does in the separability of the soul from the animal though;
I do have a small problem in your argument with the following phrase, although this is not damaging to your argument, just a complaint to do with terminology:
Back to your argument. Regrettably I can't read any more of your Source 1 than the summary because I don't have PubMed access, I'll see if I can fish around for a copy later, but this is just from the summary.
So just as pupil and sight are the eye, so, in our case, soul and body are the animal. It is quite clear then that the soul is not separable from the body, or that some parts of it are not
(413a Aristotle's De Anima II.I)
He carries on to ask whether the soul is the sailor of the boat, and so parts are very much separable, or the actuality of the boat, and not separable in any way.Developing this concept further, he hypothesized that each of us has a life force running through our blood vessels (pneuma) that allows us everything from muscle contraction to sensory perception.
It's useful to link this to Vitalism, as the theory of a life force of some form didn't stop in Greek times but carried on in relative force until the early 1900's.With his view that mind and body are separate as well as separable
Note this is a contentious point of Descartes' philosophy. Sartre's Being and Nothingness claims this is the foundation of Descartes' downfall; he should have instead considered them as a singular and looked at where their union was effected; the imagination, not by attempting to rejoin them. (pp. 27 B&N)
Descartes' reason for separating them was that it was conceivable to separate them, and so it must be possible, at least by God.
If you're interested in a more modern conception of Non-Cartesian Substance Dualism that doesn’t separate them, check out EJ Lowe's Non-Cartesian Substance Dualism and the Problem of Mental Causation: Erkenntnis (1975-) , Vol. 65, No. 1, Prospects for Dualism: Interdisciplinary Perspectives (2006), pp. 5-23
I found Erkenntnis a bit of a bastard to find, although it's on JSTOR if you have access to that.The problem was that if it truly isn’t your eyes that are seeing (but rather that the image that is reconstituted on your pineal gland so that your soul can perceive the image presented to it) then this automatically begs the question of who is seeing for your soul? Doesn’t your soul then need its own eyes and pineal gland inside of it?
What you’ve raised is known as the ‘homuncular fallacy’. Descartes replies to this directly;
“Now, when this picture [originating in the eyes] thus passes to the inside of our head, it still bears some resemblance to the objects from which it proceeds. As I have amply shown already, however, we must not think that it is by means of this resemblance that the picture causes our sensory perception of these objects—*as if there were yet other eyes within our brain with which we could perceive it*. Instead we must hold that it is the movements composing this picture which, acting directly upon our soul in so far as it is united to our body, are ordained by nature to make it have such sensations” (AT VI:130, CSM I:167).
So Descartes would probably disagree with you on the soul requiring eyes in order to see this composed object, unless this is what you meant in Descartes appears to make the soul entirely supernatural.
Assuming the homuncular argument does disprove Descartes’ argument, of which is one of the smaller problems of Descartes’ Mind-Body solution, it now must be shown that it is also applicable to modern neuroscience, which you appear to say it does by assuming it is analogous with Dualism. If it is not analogous with dualism, then the homuncular argument has no grounding what so ever, for there is no regress.
An activity is carried out in a person’s brain
Does not seem to immediately follow that a brain thinks for a distinct person, because ironically this IS begging the question, whilst mistakenly using the phrase ‘begging the question’ (See section below), that a brain and a person are separable entities; you’re using “for” to imply a separation. I feel that simply having an action carried out in my brain doesn’t necessitate that my brain also must have a brain thinking inside it; the brain appears to be the instrument by which the person thinks.
| Cognition and cogitation are functions of man, not of our brains|
This isn’t necessarily shown. Cognition is indeed a function of man, but I would argue that part of a man is his brain. Otherwise can I equally argue that picking up a rock is a function of man, not of our arms? You need stronger evidence to show a dualism between mind and man, I’m still very much convinced they are one and the same.This begs the same question that if a brain thinks for the person, who thinks for the brain?
I apologise, but unless I'm mistaken, do you not mean "invites the question"? Begging the question is a very specific form of circular reasoning which isn't present here. The other use in this article appears to be incorrect also. I am writing this out at 3AM, so I’m a little cautious about challenging it, but I figure I might as well.The Edinburgh survey revealed a predominance of dualistic attitudes emphasizing the separateness of mind and brain. In the Liège survey, younger participants, women, and those with religious beliefs were more likely to agree that the mind and brain are separate, that some spiritual part of us survives death, that each of us has a soul that is separate from the body, and to deny the physicality of mind.
Really, genuinely interesting. I wouldn't have thought dualism was that pervasive in medical attitudes, but I'm more convinced by the spiritual leanings of the summary than that people genuinely believe in the philosophical implications. This links back to my earlier concern over you jumping between the use of 'mind' and 'soul' with ease; whether someone would agree that a person has an immortal soul and whether they have a mind separable from their brain is not the same thing. You're welcome to, and I'd delight, in you challenging this. I’m really curious to see how you develop this in neodualism in neuroscience, so thank you very much for writing these articles!
And as an aside, I don't think that Aristotle was a precursor dualist. I think that he was basically on target, but that dualism can't be understood without reference to the historic continuum, of which his ideas are a giant part. Its sometimes difficult to be clear in 1500 words, but I try to keep each post at the approximate length, as I don't know if most people would read much more than that in a single sitting.
Firstly, thank you heartily for the reply. On the topic of "begs the question", I concede your point. On second read I used incorrect language, and I hope it didn't detract too much form comprehension of my broader points. Second, on your point about Descartes and his observation that our soul lacks eyes, he was absolutely right to point this out, but then he directly contradicts himself by asserting that the two images--one from each eye--must be reassembled and presented to the soul via the pineal gland, so that the soul knows what it is observing. He was on the right track, but could not see past his own misconception that soul and body are separate. This is an ideology that will always lead to failure. There is no such thing as an 'image' in the brain. This problem persists in modern neuroscience in the "binding problem", a topic I plan to cover in the next (or perhaps the third) post. In modern neuroscience, it has evolved from the homuncular fallacy to the so called mereological fallacy; that is, ascribing to a part that which can only be ascribed to the whole. I shall cover this topic in detail in post 2. This is not shown here, but please be patient; this is a series of posts in which I will address this. Picking up a rock is a function of man. I don't know if you're trying to poke holes in my argument, but I agree with this statement 100%. A disembodied arm can no more pick up a rock than a brain can think or "assemble and image". I look forward to your critique of parts two and three :)This isn’t necessarily shown. Cognition is indeed a function of man, but I would argue that part of a man is his brain. Otherwise can I equally argue that picking up a rock is a function of man, not of our arms? You need stronger evidence to show a dualism between mind and man, I’m still very much convinced they are one and the same.