Coincidentia Oppositorum

μεταβάλλον ἀναπαύεται (By changing, it remains the same.) - Heraclitus

"The more things change, the more they stay the same" (plus ça change, plus c'est la même chose), is the more contemporary version of this epigram. It's subject to a variety of interpretations. On the one hand, one may object to Heraclitus, "but if all things change, then nothing is the same." However that relies on a superficial interpretation that understands a sentence solely by means of the definition of words. Alternatively, one may rationalize the statement: if everything changes, then ipso facto it stays the same; the only constant is change. Or, despite apparent changes certain fundamental aspects or patterns remain unchanged. And indeed these are apparent facts of life, as Lewis Carroll wrote, "My dear, here we must run as fast as we can, just to stay in place." But instead of defining, and instead of rationalizing, one might consider the overall gestalt of Heraclitus' philosophy. The antinomic logic here is the key. It is a sieve through which only the knowledge that knows its own limits by means of the contrary, in a relational manner, may pass. As we'll see following a bit of elaboration, Heraclitus' gnomic utterance, which was recorded by Plotinus in his Enneads, describes the quality of the human condition, and through an understanding of this we might break out of the hall of mirrors imposed by the left hemisphere. (Particularly good news for anyone suffering from analysis paralysis and perseveration.)

The unity of opposites, as a concept, was first suggested to the western view by Heraclitus (535 – 475 BC) though the idea was nascent within the thought of Anaximander (610 - 546 BC). Because there are few records before this time, it might've been in circulation even earlier. Much later, Nicholas of Cusa (1401 – 1464) used the Latin phrase coincidentia oppositorum, meaning coincidence of opposites. CS Peirce wrote “A thing without oppositions ipso facto does not exist... existence lies in opposition.” And Carl Jung (1875 – 1961) also used the term, inspired as he was by the writings of Gerhard Dorn (1530 – 1584). But of course it is not merely a western idea. It occurs in the traditions of Tantric Hinduism and Buddhism, in Zoroastrianism, Taoism, Zen and Sufism, among others. So when Hegel (1770 – 1831) and Schelling (1775 – 1854) arrived on the scene near the inception of what would later be called process philosophy, these ideas had already been in the air for a very long time, gestating a future axiological renaissance.

I was long ago introduced to what has been called the “law of non-contradiction” and the various arguments against it by Walter Benesch, professor emeritus of philosophy, but it was Carl Jung’s intense excursions into the thought of Gerhard Dorn, which I read about in the university’s copy of his twenty volume collected works, that really seized my imagination. And so when I learned that Iain McGilchrist, who was well acquainted with many of these same thinkers, was able to naturalize their insights by placing them on a neurobiological foundation, I already had all the necessary context I needed to incorporate this most recent development in a line of thought extending back into prehistory. In a sense, Carl Jung was my gateway drug to McGilchrist. The centrality of this notion is such that it comes up quite frequently, with diverse and sometimes surprising implications, as during a recent conversation with Curt Jaimungal:

“As you know, part three of The Matter with Things, which is the whole of the second volume, is about ontology. And I begin with a chapter on the coincidence of opposites. There's a certain kind of thinking that will insist that “it's got to be one or the other”.  But actually, if you can suspend that, you can get hold of a sense which is deeper. …Think back again to love. Love is both something that recognizes an ‘other’, but comes together fully with that other, so that there is no antagonism. Without that element of something that offers a degree of resistance, nothing can be created, nothing can come into being ... opposites not only coexist, but give rise to and fulfill one another." [From the field of love (the greatest of values) we recognize the coincidence of opposites, instantiated in the fabric of our very being, and from which pours forth poetry, art, ornament, ritual, music, drama, dance… (aka "an entirely superfluous, superabundant, and exuberant outpouring of riches") The One produced the two. The two produced the three. And the three produced the ten thousand things.]

According to the Heraclitean line of thought, conflict is never overcome nor would we want it to be overcome. Instead it is to be sustained as a generative dynamic. This is challenging, as it does invert the popular perspective. The text in the image (from The Matter with Things) metaphorically points out that if we “overcome” the conflict between “the warring ends of the bow” the arrow simply falls flat. Tension is necessary. Jung found this insight valuable in psychology, and McGilchrist in neurobiology, though neither were the first in either case. (Robert Ellis has sought to eliminate conflict by supposing that it has an origination in absolutization, and while this may be true in some cases, it misses the full import of the concept.) We should be able to speak using any language capable of supplying that tension, including metaphysics or any other, so long as it is understood that these are all inadequate tools in the final analysis. And this is possible by either "thinking against thinking" (paradox) or an understanding that words are a transluscent re-presentation (poetry). As we can see, it's not the 'what' but the 'how' that matters.

If we understand Heraclitus and those following in the same tradition, they didn't want to completely integrate or resolve conflict, be that of systemic or conceptual origin, but provide a vantage from which it may be viewed. The terms complementarity, correspondence, or "coincidence" of opposites can be slightly more helpful for understanding this, as it's not a simple "unity" of opposites they describe. Consider the fundamentally opposed pair of division/union. To unify these is to beg the question: Can something really be united and yet divided? On the one hand we can clearly say no, “it's got to be one or the other”. On the other hand we can say yes. The Heraclitean view is that either response entails the other, and this is a feature or pattern that we should be able to anticipate. Equivocation is going to be unavoidable. 

These may be little more than abstractions for some, but consider how our embodiment grounds these ideas, offering an undeniable source of resistance and opposition that is provided through our contact with reality itself. Embodiment has always played a central role in this line of thought, with modern proponents, like McGilchrist above, having noted that "without that element of something that offers a degree of resistance, nothing can be created, nothing can come into being." Embodiment is no minor consideration. There is a sort of negative feedback contained within the structure of a paradox. It's as though it were a thought capable of thinking against itself. Recall "the Heraclitean view that either response entails the other," so if you turn the coincidence of opposites into a metaphysical abstraction (which no doubt many have tried to do) and yet fail to realize that this entails it is no such abstraction at all, then you never really understood it to begin with.

On the one hand, I don't think we should be perfect skeptics and hold all knowledge in doubt. But on the other hand, I don't think we should be absolutists about anything. So what remains? We could hold to a sort of milquetoast attitude of flaccid provisionality that seeks to reduce conceptual tension (Robert Ellis holds some version of this). Or we could adopt the antinomic ontology of the Heraclitean perspective, which holds that any response we give entails its own opposite. Heraclitus provided a vantage point from which we might view the conceptual tension between doubt and certainty, and adjudged this to be good. McGilchrist merely naturalized that insight in his hypothesis, expanded it to a deeper phenomenal tension, and drew out some of the broad implications. There's a sort of enantiodromia (a term favored by Jung) in culture itself, such that we don't know what good may arise out of apparent misfortune, and vice versa. Perhaps some heterodox interpretation of the hemisphere hypothesis will be that which launches it into greater public awareness, we just don't know which one that will be and how it may yet transform. 

The myths of consciousness

Decades of research suggests that consciousness is not monolithic, that it embodies qualitative differences, and that these factors in turn likely constrain its specific instantiation. But not all of these findings have filtered into the conception of consciousness that is broadly held within contemporary society. In part this may be because it represents a challenge to several popular myths. The hemisphere hypothesis in particular, which draws upon this body of research, takes direct target at each of these:

Myth 1: Consciousness is monolithic and entire of itself. This is the idea that our experience of unitary awareness cannot be described as a synthesis of several identifiable neurological processes. The hemisphere hypothesis challenges this myth by suggesting that there are in fact at least two primary holarchic processes, that these are instantiated in the hemispheres, and that their combined interactions influence conscious (and unconscious) mental processes.

Myth 2: Consciousness has no polar attributes. This is the idea that our experience has no relation to qualitative differences in attention, specifically axiological differences with corresponding normative/ ethical implications. The hemisphere hypothesis challenges this myth by suggesting that there are at least two primary forms of attention that are coincident and yet not completely reconcilable to each other, and which reveal polarized differences in the quality of awareness. [2] (Polarity may be negatively defined as asymmetry or inequality.)

Myth 3: Consciousness is substrate independent. This is the idea that the particular embodied substrate (and perhaps structure and form) of mental experience is fundamentally irrelevant. And accordingly we could abstract and reproduce consciousness in silicon, digital, or any other suitable Turing-complete format. The hemisphere hypothesis does not completely refute this "myth," but it does impose strict constraints on any suitable substrate in the sense that, as far as we know, it would need to recapitulate those embodied processes that permit neurological opponent processing.

As popular myths, these are the main principled objections I've encountered preventing a wider application of the hemisphere hypothesis (prejudices relating to presentation and confusion regarding derivative implications may be addressed elsewhere). As long as these continue to have their hold, the hemisphere hypothesis will be outright dismissed. And many of the primary implications that follow from it, such as asymmetry and paradox, will remain substantially incomprehensible, at least when applied to phenomenal experience. Some prior familiarity with any of the currently extant antinomic ontologies (many Eastern traditions, Heraclitean, Jungian, process philosophies, indigenous traditions, etc.) can be of benefit when addressing these contemporary myths; if one is already familiar with paradox in philosophy, then one may be less surprised when they find it turns up in biology as well. The remaining obstacles to a more comprehensive understanding are for the most part comparatively minor technical details, and can be sorted out using the conceptual tools available to us.

I put those three main myths down as I have because I had just finished having an extended conversation with several people who were antagonistic to McGilchrist and his work. Unsatisfied, I wondered why no substantial movement by anyone resulted upon its conclusion. As is often the case, most of the objections they raised, and rejoinders I provided, failed to get down to, as Jonathan Rowson puts it, “what’s at stake here,” or in other words, what cherished ideas are really being threatened. I think these contemporary myths are precisely what McGilchrist is threatening, and what he simply cannot be allowed to overturn.

What I am seeking to do is identify and remove whatever is occluding our vision or preventing us from recognizing and presencing to the reality of our situation. I think these myths could be seen to lie near the heart of it. And I’m using the term "myth" in the pejorative sense that it has today, because this is the most common way in which it is used by most people. I'm aware that there is a more accurate sense of the word that McGilchrist usually intends when uses it. Such myths (or I should say, cognitive biases) often lie below our everyday awareness, keeping us blind until confronted and dealt with.

There’s been growing recognition from various quarters about several trends converging in the same direction that McGilchrist is pointing. There's a revival of panpsychism in philosophy, a revival in a biological basis for teleology, via the Extended Evolutionary Synthesis, and a revival of appreciation for the sacred and corresponding decline in “new atheism” (which some have speculated may have been fueled by the cultural response to 9/11). And now with McGilchrist, there’s a growing awareness of the unity of the sciences and humanities, and more besides. None of this is coming a moment too soon! The view that emerges from all this is one which reassures us that we do not have to abandon any proclivity we may have for "hardcore materialist reductionist" explanations. It merely asks us to expand our weltanschauung so that it is able to encompass the alternate perspective as well. There is, we are told, room enough for both of these within us.

Mind and Matter

Panpsychism has become a familiar view, both within philosophy and popular culture. And it's less associated with McGilchrist than it is with its more vocal proponents, like Philip Goff or (to a much lesser extent) Michael Levin. In my experience, panpsychism is not often raised as a cause for objecting to the hemisphere hypothesis (as compared to the myths described above). I've not heard, for example, "I agree with everything McGilchrist says about the hemispheres, the two modes of attention and all that, but panpsychism is simply a bridge too far." A simple inversion between matter and consciousness, as to which is more ontologically primitive, is a conceptually easy enough flip for most people to do. After all, the core notions of idealism were proposed long before Berkeley's 1710 A Treatise Concerning the Principles of Human Knowledge. And variations have been a plot device in many popular films. In his book Descartes' Baby, psychologist Paul Bloom describes children as natural dualists. The subsequent reduction of mind to matter (or vice versa) is the sort of simple operation that the left hemisphere excels in.

But on the other hand, panpsychism could be so outrageous of an idea that, like McGilchirst's notions of the sacred and other metaphysical concepts, it needn't even be raised at first. At least, that is, without either first addressing the less esoteric seeming ideas that are specific to the hemisphere hypothesis (the rational/ scientific approach), or without first directly contacting such a reality and thereby breathing life into the idea (the intuitive/ imaginative approach). When approached rationally, asking a materialist to jump straight into panpsychism is probably putting the cart before the horse. Such a conclusion may be better thought of as lying at or near the end point of a long line of argumentation, along with the other implications of the hypothesis that only become rationally plausible once assent is first granted to the basic premise: that the brain's form and structure reflects complementary, though divergent, modes of attention.

For those who are antagonistic toward any version of panpsychism, beginning there would likely shut down further engagement with the hemisphere hypothesis that might've otherwise been possible. Can we begin with panpsychism as an initial premise, then from there arrive at the hemisphere hypothesis? I'm not aware of anyone doing so. And the reason may be that this is because we live in a culture whose dominant premise is materialism, not panpsychism. But the rational/ scientific approach could likely follow either direction, to convince the materialist of panpsychism, or the panpsychist of materialism. In other words, without addressing the neurological argument for opponent processing first, the possibility of such alternative arrangements remain for the most part conceptually incoherent.

But ultimately, McGilchrist's hemisphere hypothesis may be best understood as a post hoc explanation (as are all discursive approaches). In other words, the real work of convincing us of the reality of any metaphysical considerations takes place through direct experience. This is the previously mentioned intuitive/ imaginative approach. Accordingly, one might say "These arguments will not do the work of convincing you, or anyone else, for that you must experience the divine yourself. But they will enable you to understand how it is that you were able to presence to the sacred to begin with." That being said, the virtue of the post hoc rational approach is that by opening a door into RH translucency we are able to subvert our own LH opacity. And using both approaches in tandem we come that much nearer to the possibility of addressing the neglect, denial, and indifference that characterizes our relationship with much of the world today.

Scott Barry Kaufman's opposition: DMN & TPN

The topic of the Default Mode Network (DMN) has been raised in some discussions we've had, regarding how it might correlate with the function of the right hemisphere. So it was interesting to hear that the DMN was recently also discussed on the Many Minds podcast during an interview with Ev Fedorenko about a review paper she wrote:

Fedorenko: "This default network is a network that has been implicated in building up these long contextual representations. It can be happening when you’re watching, say, a silent film where there’s no language whatsoever, but you’re still constructing this long narrative structure, but also when you’re listening to a story, which, of course, is linguistic but engages this system which is not specific to language. It’s an interesting system but I think needs more work to understand."

Has this subject been discussed by McGilchrist? Tangentially. Paraphrasing an earlier interview with Scott Barry Kaufman:

Kaufman: “Our work is actually really consistent. We should coauthor an article together.”

McGilchrist: “That would be great.”

Kaufman: “I’m obsessed with the default mode brain network because I think that network offers us the core of human experience of what it means to be really human. And I think you’re obsessed with the right hemisphere for the same reason. So I looked deeper into our Nature paper and I noticed that there were preferential right hemisphere activations in the default mode network. Now, we didn’t originally set out to test that specifically, so don’t quote me on that as a statistically significant effect, because we didn’t have the methodology, but I noticed a trend…

It’s mapping the ‘network approach’ to the ‘hemisphere approach’. You’ve got me thinking about this in a deeper way than I ever have before, how these are probably both saying the same thing. They’re just different levels of analysis. You know, I’ve been arguing against the tyranny of the executive attention network, where you’ve been arguing against the tyranny of the left hemisphere. But conceptually, I feel like we’re both bothered by the same thing.”

McGilchrist: “I think that that’s right. There’s a lot of overlap.”

I would love to see such a paper, if it were to be written. 

Any discussion of the DMN and the anti-correlated Task Positive Network (aka "executive attention network") might cause one to wonder if McGilchirst is like that proverbial "man who was found searching for his keys, not where he had dropped them, but under the lamplight, because that was where he had enough light to search." The location of damaged brain regions, whether on the left or right, has long been noted in lesion-deficit studies, so it would obviously be easier to articulate a hypothesis about the hemispheric lateralization of our modes of attention. Those same studies do not necessarily "shine a light" on whether portions of the DMN or TPN are damaged or not. Consequently this lack of information prevents the likelihood of a possible "Network Hypothesis" from being put forward as a competing theory to the "Hemisphere Hypothesis". After all, the DMN was only described in 2001, with the majority of papers published after 2007, so there wasn't a whole lot of research at the time of the publication of The Master and His Emissary in 2009.

Now, if information about these brain networks should prove to be more explanatory than the hemisphere hypothesis, would this invalidate the sort of arguments that McGilchrist is putting forward in his work? Not necessarily. It's conceivable that it would merely switch the attribution of his observations to a different neurological mapping, that is, from hemispheres to networks.

Kaufman and McGilchrist are engaged in complimentary research. And as he indicated, the most likely possibility is that one level of analysis is at a higher integrative level [1] than the other, one of these can only be fully developed by seeing it in light of the other, located at a higher integrative level. If they were to write a paper comparing the network and hemisphere approaches, I suspect they might find just this sort of hierarchical relationship, such that one is "necessary but not sufficient," one of these underwrites critical aspects of the other, but does not explain the full observations. But which is it? 

Is it more accurate to say that each hemisphere has access to bilaterally distributed networks with anti-correlated roles? Or is it more accurate to say that these networks cut across hemispheric divisions to access lateralized hemispheres with anti-correlated modes of attention? Whichever it is, this is the "what."

Following that, "how" these neurological networks are engaged by either hemisphere in the deployment of asymmetric modes of attention is the purview of the hemisphere hypothesis. Or conversely, "how" these hemispheres are engaged by either network in the deployment of asymmetric roles is the purview of the network approach. So is the lateralization aspect overlain upon the network approach, or vice versa?

In the conclusion of The Master and His Emissary, McGilchrist writes that the "divided nature of mental experience... might have some literal truth." If we assent this much, then does it really matter which "chunks" of the brain "mirror the dichotomies that are being pointed to"? In principle, I don't think it should. Both analyses involve opponent process theory (anti-correlated networks or hemispheres) with asymmetric roles. The 'coincidence of complementary opposites' is the primary insight. In order to be 'antifragile' and adaptable the brain operates near a critical threshold at the edge of chaos, between order and disorder (or so it's been speculated), which is the most resilient place to be. Exactly where these coinciding oppositions are instantiated is arguably of secondary importance.

A point in favor of the network approach is that it does more easily satisfy the "bridge law objection" as articulated by Spezio (and referenced by Thompson) because it appears to better identify a reductive "locus" for various features. It also better comports with a postmodern cultural context, in part because it is more conceptually abstract, and because an eliminativist perspective (which is where the network approach tends to lead) means one can avoid addressing the question of how science and the humanities intersect, a preferable outcome since it is feared that any proposed answer to that question might support discriminatory practices and revisit the experience of historical traumas. 

McGilchrist noted that Marcel Kinsbourne identified three main oppositional pairings within the brain. The network approach described by Kaufman here articulates still others in addition to these, or perhaps merely recombines and reinterprets them in different formulations, subdivided at different scales of resolution. And this is to be expected. We should not be surprised to find a multitude of opponent pairings across many scales and within a wide variety of biological systems. 

A point in favor of the hemisphere hypothesis is that, and here McGilchrist cites Joseph Bogen, "hemispheres can sustain the activity of two separate spheres of consciousness." The network approach cannot claim this as easily. In part this is due to the inherent complexity of the networked neurological structures being described and their morphological dissimilarity to each other. I think we are now able to postulate a few general rules: 

• Once structural complexity has reached an apex or point of diminishing returns, mutually entailed opponent processing must take over to do what elaborate complexity cannot achieve alone, for example, in order to be able to address problems such as those raised by the "no free lunch" theorem. McGilchrist shares the Heraclitean view: "We need resistance. We need opposition."
• The highest integrative level or scale of opponent processes will provide the greatest explanatory power, as these are the "highest leverage points" (Donella Meadows) in the system. These large scale dynamics exert downward constraint that entrains and thereby overrides lower scale differences (Stanley Salthe). This also suggests an apparent telos or convergent drive acting behind the system to sustain opponent dynamics. 
• In general, the higher the level of opposition, the more evenly matched 'the agonist and the antagonist' may appear to be. This is needed in order to sustain the tension between them. Lower level analyses however tend to focus on similarities among the parts instead of the higher level opposed gestalten. (Thus to a trained eye, the apparent redundancies in the bisected brain should suggest that a higher level of integrated opponent processing may be occurring, with corresponding phenomenological specialization.)

And indeed, these implications appear to follow from the underlying argument in The Matter with Things, which leads from neurology to "naturalized metaphysics" in a single vision, re-uniting the sciences and the humanities. 

Bernardo Kastrup's opposition: Intuition & Reason

A recent conversation between McGilchrist and Bernardo Kastrup illustrates important places of convergence and divergence. Kastrup's framing of cognition is more orthodox than McGilchrist's, and I suspect Evan Thompson is more sympathetic to Kastrup's description here as well. A few excerpts:


McGilchrist: “I believe that what we experience is the real deal. It doesn't mean that it's the whole truth about whatever it is. It's just that that is a real experience. It is the experience that I had of that particular thing, as it were, five o'clock in the afternoon.”

Kastrup: “Evolution would never optimize for us to perceive the world as it is. It would optimize for us to see the world in whatever way it would be more conducive to fitness. So “fitness oriented perception” stands to be very different from perception that mirrors the states of the world... The qualities of perception represent what it is like to observe the world, and what it is like to observe the world is different from what it is like to be the world. And that's why representations and the world “as it is in itself” may deviate.”

McGilchrist: “For a lot of things you feel your way into them. And people may say, well, you do that through your senses. Okay, but in fact you do it by an act of imagination. And having spent many years practicing as a psychiatrist, I spent a lot of time sitting with people and understanding what it must be like to be them. What is it like to be that person? And indeed, in all our lives, we're doing this all the time, and it's how love originates. You feel your way into, way beyond anything that you can write down as a perception about somebody. And you really do feel as if you're making contact with them. The reality of those experiences have shaped who I am. There is this reciprocal encounter in which I contribute to what there is other than me, and this other than me also contributes to making me who I am... it can be argued that imagination is the only way to understand in depth what it is that one is attending to.”

Kastrup: “Human reasoning is the latest cognitive capacity we've evolved. From very early on life had the capacity to express spontaneous intelligence, intuition, and imagination. Those are the early ones. If you think of a human being as a tree, intuition and imagination are at the root. It's what makes contact between us and reality. And thinking is all the way in the canopy. It’s in the clouds. It's all conceptual. It may be the most advanced, but it's also the youngest and the most removed from the ground of reality. And typically it's people like me, who have the other mental faculties stunted, that put reason above everything else because then they can then self-validate. It’s a kind of self-deceptive game. …The universe is computationally irreducible. The only way to know is to get there. And I think that's the whole point of existence is to set it in motion.”

McGilchrist: “Metacognition is a very late arrival on the scene, as you say, and I'm not sure that it is necessarily a help. And one of the reasons I say that is that the very interesting question which you raised of the savant. A savant may be born with special skills of this kind, or may suddenly have access to these skills, never before having had access, after brain injury. And what interests me is it's almost always an injury to the left hemisphere. Now, the left hemisphere is mainly interested in self-reflective forms. The right hemisphere is more open to the breadth, but the left hemisphere is very much inwardly focused. That Gorgon stare of the left hemisphere... (Kastrup: It casts a field of obfuscation around it. It's like staring at the sun at noon and missing all the stars, because the glare of metacognition is just too strong.) It's definitely a trade off. As long as it doesn't rule the show, we can reel it in at a certain part of the process of coming to understand something, and it will illuminate things. But at the end, we must lose the focus of that again in order to discover the reality of the whole. So we go from a whole that gets broken down and over focused by the left hemisphere to an understanding of the whole again in the right hemisphere.” 

Recall that for McGilchrist the defining opposition in the brain was present long ago. As he wrote, “the earliest known instance of a nervous system, that of Nematostella vectensis, a sea anemone over 700 million years old, already exhibits lateral asymmetry.” This asymmetry corresponds to the two complementary modes of attention that we see in ourselves today. Why is it so important for McGilchrist to trace this back millions of years? He suggested it is because all life must know how to “eat without being eaten.” Though perhaps true, this always felt like a bit of an ad hoc explanation to me intended to satisfy a certain type of reader. Which is why I think Zak Stein gets closer to a deeper metaphysical point when he referenced Whitehead, remarking that "life emerged to respond to value, which pre-existed it. That the evolutionary process responds to value makes it teleological.” Or in other words, Stein recognizes that McGilchrist really wants to tie the structure of the brain to the very structure of reality itself. Neurological asymmetry is an evolutionarily conserved feature because neurology recapitulates ontology. Whitehead's "appetition of the cosmos" is a positive definition of life. We aren’t here just to avoid being eaten while we search for the next meal.

As for Kastrup, in this conversation he points to a different opposition within the brain, between intuition/imagination on the one hand and reason/metacognition on the other. And he lays emphasis on the relatively recent arrival of reason/metacognition to the evolutionary scene. While it is undeniably true that other species do not display these capacities in the same ways that humans have, I think Kastrup’s view here may be a bit too focused on one side of the equation. We could recall the intelligence of slime molds and plants, which has caused scientists to wonder how widespread such problem solving capacities are in the natural world. But more to the point, we may equally wonder if it might be that our capacity for intuition and imagination never really stopped developing, and has continued to expand in lockstep with those vaunted capacities for reason and metacognition, displaying an equal increase in range and depth over evolutionary time. It is this latter possibility which McGilchrist seems to be hinting at above. 

References: 

[1] Joe Scott described 'top down' causation in a recent video: "There's not just one consciousness going on inside our minds. There's two. But it actually gets crazier. Turns out there's actually multiple modules inside each of the hemispheres that can display a kind of consciousness, and they have their own things to say. In a lot of ways, our brains work pretty much like a hierarchical brain system. Consciousness is a result of both 'bottom up' and 'top down' causation. We are simultaneously making decisions on a subconscious level but also shaping those decisions at a conscious level. In Gazzaniga's words, "Action is made up of complementary components arising from within and without... What is going on is the match between our ever present multiple mental states and the impinging contextual forces within which it functions."

Tania Lombrozo: "One way to think about how 'learning by thinking' occurs is to basically say that your mind has multiple components, and like, one part of your mind knew something, but the other part of your mind didn't know that, so the way that 'learning by thinking' works is that part one tells part two, and now part two learns something that it didn't know before. ...If you think about the mind itself as possessing kind of multiple sub-minds, sub-mechanisms, sub-components, and so on that can communicate with each other, and share information with each other more or less effectively, then a lot of the same ways that we think about information transmission working within groups of people apply to what what we think about what happens within the human mind. ...To what extent is it that we see those kinds of "many minds" within a single mind?"
Kensy Cooperrider: "That is a new gloss on the title of our podcast Many Minds. I never thought of that as referring to the many minds within a single mind."

Iain McGilchrist. The Coincidence of Opposites (2021) "I've argued that at the origin of everything there lies a coincidence or conjunction of opposites that is profoundly generative, indeed necessary for creation, gives rise to all that we know. And this coincidence of opposites is by no means contrary to reason. I've stressed that we must not be tempted, in a left hemisphere fashion, to resolve the necessary tension by pretending one of the pairs of opposites can safely be dispensed with, or is not real. Denying the concealed opposite is dangerous. The coincidence of opposites does not compromise their nature as opposites, rather they fulfill themselves through one another. The foundation of everything, recognized from Empedocles to Goethe, is this opposition between love and strife. We need the union of division and union, the union of multiplicity and unity... [and] just as there's an asymmetry in the relationship of the hemispheres, there's an asymmetry in the coincidencia oppositorum." 

Iain McGilchrist. ‘Selving’ and Union (2016) "It is no contradiction that, while the idea of the self as distinct from others does have meaning, the dichotomy between self and others is fundamentally misleading. From the outset they are intertwined, proceed from and return to one another. They could be said to ‘co-create’ each other: ‘The sense of self emerges from the activity of the brain in interaction with other selves.’ ...it may come to life in a Hegelian sense: for the emerging product may be neither just both, nor neither, of two contraries we cannot singly embrace, but something new altogether, as the lyric tone of the lyre emerges from the tension of the wire that holds its warring ends together."

Iain McGilchrist. The Matter with Things (2021) “...opposites not only co-exist, but give rise to and fulfil one another (‘sunt complementa’), and are conjoined (like the poles of a magnet) without any intervening boundary, while nonetheless remaining distinct as opposites. And indeed the more intimately they are united, the more, not the less, they are differentiated. [...] Blake famously wrote: "He who would do good to another must do it in minute particulars. General good is the plea of the scoundrel, hypocrite and flatterer, for art and science cannot exist but in minutely organised particulars and not in generalising demonstrations of the rational power. The infinite alone resides in definite and determinate identity." The point Blake is making is that we do not come to understand or experience the infinite, or, for that matter, the eternal, by attempting somehow to transcend the finite or the temporal, but by immersing ourselves in them, in such a way as to pass into the infinite, manifest there where they are. The path to the infinite and eternal lies in, not away from – not even to one side of – the finite and the temporal.”

[2] Àlex Gómez-Marín: "For Whitehead, nature is made of "events" not of substances. And those events are polar. Imagine something that happens in the world, that gets "actualized." It has a future and a past pole, a mental and a physical pole. You might say that's substance dualism, but it's more sophisticated than that."

In the Andean worldview, life is made possible through a generative encounter (tinkuy) between opposite complementary forces (yanantin). Female and male bodies are an expression of this duality. 

Alan Watts. The Two Hands of God: The Myths of Polarity (1963)