This Landscape of Consciousness (LoC) website presents over 350 theories (explanations) of consciousness, organizes them into a suggested taxonomy, and explores their implications for big questions, such as AI consciousness and life after death.
Five ways to access and visualize all categories and theories of consciousness (plus Search and Ask AI).
All theories in all images/graphics are linked to their theory page. Just click on them.
This LoC website is an extension, expansion, and revision of my review paper, “A Landscape of Consciousness: Toward a Taxonomy of Explanations and Implications” (Kuhn, 2024), which was published in Progress in Biophysics and Molecular Biology (Vol. 190, August 2024). In the paper, I seek an organizing framework for diverse theories of consciousness and to explore their impact on big questions. My central theses are twofold: (i) understanding consciousness at this point cannot be limited to selected ways of thinking or knowing, but should seek expansive yet rational diversity, and (ii) issues such as AI consciousness, virtual immortality, meaning/purpose/value, life after death, free will, etc., cannot be understood except in the light of particular theories of consciousness.[1]
Àlex Gómez-Marín reviewed the paper on IAI News. SciTechDaily report. I describe Landscape in an FQxI blog (Foundational Questions Institute).
I have appreciated all the comments, suggestions, and critiques from colleagues and global readers, and much of the extension and expansion of this LoC website is derived from such feedback on the LoC paper.
The focus here on the LoC website, as in the LoC paper, is ontological: what is the essence of our inner subjectivity, our awareness, our felt experience—what generates our perceiving, our enjoying, that which we call qualia?
The suggested taxonomy arrays the >350 theories into 10 categories—one of which, Materialism, has 12 subcategories. Each theory has its own page and description, and to get an overall sense of this rather vast territory, we offer five ways to visualize the Landscape and to access each theory (plus Search and Ask AI).
The theories skew toward contemporary and scientific theories, but I remain committed to trying to reflect the collective wisdom of humanity across time and cultures, though constraints are obvious. While I myself am not a consciousness practitioner, as it were (I do not meditate or take psychedelics—I play intense table tennis!), I have a lifelong and unremitting passion to understand consciousness.
I distinguish what consciousness is ontologically from how consciousness happens operationally. The Landscape I present is populated primarily by claims of what consciousness actually is, not so much how it functions and how it evolved over deep time (although both how it functions and how it evolved may well reflect what it is). This is not a landscape of how consciousness emerged or its purpose or its content—sensations, perceptions, cognitions, emotions, language—none of these—although all of these are recruited by various explanations on offer.
Mechanisms of consciousness are relevant here only to the extent that they elucidate a core theory of consciousness. For example, the 'neurogeographic' debate between the 'front of the head' folks—the Global Workspace and Higher-Order theorists—and the 'back of the head' folks—the Integrated Information and Recurrent Processing theorists—may be essential for a complete neurobiological explanation of consciousness (Block, 2023, pp. 417–418), but it is of only mild interest for an ontological survey of the Landscape. If the Global Workplace suddenly shifted to the back of the head and Integrated Information to the front, would the 'trading-places' inversion make much of an ontological difference?
Traditionally and simplistically, the clash is between materialism/physicalism and dualism or idealism? Could such oversimplification be part of the problem? Other categories and subcategories, I submit, have standing.
The alternative theories of consciousness that follow come about via my hundreds of conversations and decades of readings and night-musings. As noted, I offer 10 categories of theories (explanations) of consciousness; all but one present multiple specific theories directly; only Materialism has subcategories.
Here are the 10 primary categories of theories: Materialism (with 12 subcategories); Non-Reductive Physicalism; Quantum & Dimensions; Information; Panpsychisms; Monisms; Dualisms; Idealisms; Anomalous & Altered States Theories; Challenge.
It is no surprise that Materialism has by far the largest number of specific theories. It is the only category with a three-level organization: there are 12 subcategories under Materialism, each housing eight to 16 specific theories. This makes sense in that there are more ways to explain consciousness with neurobiological and other physical models than with non-neurobiological and non-physical models, and also in that the challenge for materialism is to account for how the physical brain generates mental states (and there are increasingly innovative and diverse claims to do so).
There is obvious overlap among categories and among theories within categories, and it is often challenging to pick distinguishing traits to classify theories in such a two-dimensional, artificial, and imposed typology. For example, one can well argue that Non-Reductive Physicalism, Quantum & Dimensions, and perhaps even Information and Panpsychisms, are all, in essence, materialist theories, in that they do not require anything beyond the physical world (whether in current or modestly extended form). I break out these categories because, in recent times, each has developed a certain independence, prominence, and credibility (at least in the sense of the credulity of adherents), and because they differ sufficiently from classic Materialism theories, exemplified by the fundamental laws of physics (as we know them) and neurobiological mechanisms.
Moreover, there are many ways to envision a landscape, of course, and, as a result, many ways to array theories. I claim no privileged view. In addition, while each theory is assigned to a single category on the Landscape, the categories are not mutually exclusive, such that theories may well fall into several categories, but attempting to introduce even secondary categories would add dizzying complexity to a landscape that is already rather complex. For example, Joachim Kepper states, "In the case of my theory, the leading category is, quite rightly, 'Quantum & Dimensions.' At the same time, my theory is also compatible with panpsychism (cosmopsychism) and dual-aspect monism, which could be regarded as valid secondary categories."
Here's another example of the complexities, and even the ambiguities, of classifying theories of consciousness. In response to the Landscape summary of her theory, “Gefter’s Enactive-QBist Engagement,” science philosopher/writer Amanda Gefter, a friend and colleague, wrote to me [RLK] to make an important point (reproduced with her permission).
“I don't consider my view, or enaction in general, to fall under materialism. But it's a nuanced point, because it's certainly not idealist or dualist either. The way I think about it is that materialism and idealism, to even be formulated as categories in the first place, require an absolute subject-object split. That way, the idealists can take the subject side as foundational and the object side as emergent, the materialists can do the reverse, and dualists can take some of each. But by rejecting the absoluteness of that split in the first place, enaction (and QBism) doesn't operate within those categories. It's not all first person (like idealism) or all third person (like materialism) but something more like second person, where the split itself is enacted in a participatory way. Some forms of embodied cognition are perhaps more comfortably categorized as materialist if they take the body itself as a given, as an object. But enaction describes cognition and sense-making as processes through which the body makes itself in participation with the world, so the body is an ongoing verb rather than a pregiven noun. By enacting itself, the body is functioning as both subject and object, and doesn't fit squarely in either one alone.”
I [RLK] responded with appreciation, recognizing that Amanda makes a critical distinction in classifying enactivism from a subject-object framework—and joked that in classifying theories of consciousness, instead of being restricted to a 2D map/grid, if I had, say, Hilbert Space, I could do a better job. I explained that my approach to Materialism as a category is based on fundamental ontology and framed rather simplistically, defined in the negative. If there is nothing in the theory that is outside the bounds of current physics, it is Materialism. Enactivists, to my knowledge, take pains to stress that there is nothing spooky or non-material in their theories. (Qbism, on the other hand, I would not classify as under Materialism.) I do break out “Non-Reductive Physicalism” and “Quantum & Dimensional” as categories separate from Materialism— even though they have physicalist ontologies—because they offer a different or radically enlarged view of the physical. So, I cannot claim a logically precise demarcation between where Materialist theories stop and Non-Materialist theories begin—I’m simply satisficing, given the constraints, as best I can. I do stress that I am presenting “A Landscape,” not “The Landscape,” in that there are alternative classification schemes equally valid.
Another complexity is that the ideas of epiphenomenalism, functionalism, emergence, mind-brain identity, and supervenience, and the mechanisms of prediction and language models, while themselves not specific explanations of consciousness, represent core concepts in philosophy of mind that can affect many explanations and influence many implications.
Some would impose an 'entrance requirement' on the Landscape, such that theories admitted need be 'scientific' in the sense that the scientific method should be applicable, whether in a formal Popperian falsification sense or with a weaker verification methodology. I do not subscribe to this limitation, although we must always distinguish between science and philosophy, along with other potential forms of knowledge. (My quasi-“Overton Window” of consciousness—i.e., the range of explanatory theories I feel comfortable presenting, if not endorsing—may be wider than those of others, whether physicalists or nonphysicalists[2] [Birch, 2023]. One reason for my wider window is the unsolicited theories of consciousness I receive on Closer To Truth, some of which I find intriguing, if not convincing.)
Here’s the backstory. The journal, Progress in Biophysics and Molecular Biology (PBMB), invited me to write an article on consciousness broadly. (I was reluctant, imagining what it would entail—even so, I wildly underestimated.) In my first draft, I included, along with all the hard and speculative science, philosophical and theological explanations: complex philosophical theories (e.g., non-reductive physicalism, emergent dualism, cosmopsychism) and diverse religious theories (i.e., Hindu, Buddhist, Daoist, Judaic, Christian, Islamic, Indigenous). The anonymous peer reviewer, while generously appreciative of the scientific theories (and offering helpful suggestions), recommended cutting the purely philosophical and theological theories—which, he said, journal readers would not much care about. I responded by agreeing that journal readers would likely not care, but that I surely did care, and because I was going to do this Landscape once in my life, I must make it as complete as I, in my idiosyncratic way, saw fit. If PBMB did not want to publish it with all the theories, I’d totally understand and seek another venue. To PBMB’s credit, they agreed to publish it all, nothing cut.
The Landscape itself, as a two-dimensional typology, is limited, and imperfect decisions must be made: which theories to include and which not; where to classify; what is the optimal order; whether to append a possessive name to the theory's title; and the like. I've tried to include all the well-known theories and an idiosyncratic selection of lesser-known theories that have some aspects of originality, rationality, coherence, and, well, charm.
In addition, a few theories reflect the beliefs of common people, or the interests of Closer To Truth viewers, though they are largely dismissed by the scientific and philosophical communities. Some theories, some think bizarre, 'fabulous' in the original pejorative meaning of the word: mythical, celebrated in fable. All reflect the imaginations of the human mind, driven by a quest to know reality in general and the nature of consciousness in particular.
Please do not take the unavoidable appearance of visual inequality among theories as indicating their truth-value equivalence (or, for that matter, my personal opinion of them).
Neuroscientist Joseph LeDoux, noting “the broad nature” of the Landscape (on reviewing an early draft), suggests that “The Sniff Test” might be relevant. (He uses The Sniff Test to assess the strong AI view substituting 'consciousness' for 'intelligence' [LeDoux, 2023a, p. 301].) I'm all for imposing an olfactory hurdle for theories of consciousness (recognizing that olfactory bulbs do differ).
As I have appreciated all the feedback I have received on the LoC article, I will appreciate continuing feedback on this LoC website. Feedback is most welcome, suggestions and critiques, of course—including explanations or theories of consciousness that are not included, or not described accurately, or not classified properly; also, improvements to the classification typology.
Nothing is sacrosanct. We look forward to providing updates and making revisions. This Landscape of Consciousness website is a work-in-progress—permanently.
To reiterate, the rough flow of the theories arraying the Landscape of Consciousness—as per my idiosyncratic approach—is on a rough, arbitrarily linear, physicalism-to-nonphysicalism spectrum from, to begin with, most physical, and to end with, most nonphysical (or least physical).
Again, there are five ways to access and visualize all categories and theories of consciousness (plus Search and Ask AI).
Landscape Grid. Landscape Categories. All Landscape Theories. Landscape Map. Interactive Visualizations.
All theories in all images/graphics are linked to their theory page. Just click on them.
Footnotes
[1]. Some sections are derived or adapted from my earlier article: Kuhn, Robert Lawrence (2016a). Virtual Immortality. Skeptic Magazine, Volume 21, Number 2, 2016.
[2]. “In politics, the ‘Overton window’ is the range of positions that politicians can safely raise in public discourse. Propose something outside the window, and you can expect resistance—not just to the proposal itself, but to the idea that, after saying what you just said, you even merit a place in the debate. Science too, has Overton windows. Sometimes positions can be so far outside the mainstream that they invite the charge that we should not even be discussing this” (Birch, 2023).