Head to head
Nagel’s Mind and Cosmos vs Sam Harris
Nagel's Mind and Cosmos and S. Harris’s Mystery of Consciousness, compared field by field from their entries in the Atlas.
At a glance
- Both belong to the Challenge family in Kuhn's Landscape of Consciousness.
- They give the same kind of answer on mind uploading.
- On AI consciousness, Nagel’s Mind and Cosmos says “Uncertain” and Sam Harris says “No”.
- On life after death, Nagel’s Mind and Cosmos says “Conditional” and Sam Harris says “No”.
- On meaning and purpose, Nagel’s Mind and Cosmos says “Cosmic/Ultimate” and Sam Harris says “Humanistic only”.
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The claim
In brief
Nagel’s Mind and CosmosThis perspective challenges the prevailing materialist Neo-Darwinian conception of nature, arguing that it fails to account for the irreducible nature of subjective experience, or 'what it is like' to be a conscious organism. It proposes that mind must be incorporated as a fundamental principle of nature itself.
Sam HarrisThis perspective, offered as a challenge rather than a prescriptive theory, frames consciousness as an unbridgeable mystery that cannot be solved by purely physical means. Harris argues that physical descriptions are 'mute' regarding subjective experience; the only thing attesting to sentience is consciousness itself, creating a fundamental explanatory gap. He remains pessimistic that science can dispel this mystery.
What consciousness is
Nagel’s Mind and CosmosConsciousness is fundamentally subjective experience—'how it is for the subject himself'—which resists reduction to purely physical, third-person descriptions.
Sam HarrisConsciousness is identified as subjectivity or sentience, which is fundamentally mysterious and unexplainable by purely physical processes.
Big questions
Can AI be conscious?Differ
Nagel’s Mind and CosmosUncertainAs a critique of functionalism and reductionism, Nagel's view suggests that purely computational entities lacking fundamental mental properties are likely philosophical zombies; outcome depends on whether future AI can instantiate the hypothesized universal mental principles.
Sam HarrisNoIf consciousness is irreducible subjectivity missing from physical descriptions, then advanced computation (AI, which is purely physical complexity) will fail to generate genuine sentience.
Nagel’s Mind and CosmosConditionalIf consciousness is a universal, fundamental property rather than a biological emergent, its essence may persist after bodily dissolution (inferred from panpsychist leanings), though likely without retention of personal identity.
Sam HarrisNoAs a naturalist, Harris implicitly aligns with the view that consciousness is tied to the physical organism, meaning its termination results in permanent non-existence, despite the mystery of its nature while alive.
Could a mind be uploaded?Both agree
Nagel’s Mind and CosmosUnlikelyThe irreducibility of subjective experience means duplication of physical/functional patterns alone would fail to transfer the original first-person consciousness.
Sam HarrisNoIf consciousness cannot be explained by purely physical processes, then duplication or uploading of the physical substrate will fail to capture or recreate the essential subjective self.
Nagel’s Mind and CosmosCosmic/UltimateExplicitly seeks to incorporate mind as a fundamental natural principle to overcome the 'pointlessness' implied by materialism, suggesting a non-theistic, inherent cosmic purpose or value.
Sam HarrisHumanistic onlyThe mystery does not imply cosmic purpose, but Harris advocates finding personal truths through introspection, aligning with self-discovered (naturalized) spirituality and meaning.
Nature of mind
Ontology
Nagel’s Mind and CosmosPhilosophical Challenge (leaning towards Universal Monism/Panpsychism)
Sam HarrisSkeptical/Mysterianism (Justified: The view asserts the philosophical intractability and unbridgeable nature of the mind-body problem, aligning with core tenets of mysterianism, though without adopting a specific alternative ontology.)
Mind and body
Nagel’s Mind and CosmosCritiques the current conception of the mind-body relationship, asserting that we lack any conception of how physical and phenomenological aspects could be related or identical.
Sam HarrisUnbridgeable Gap / Non-reductive Correlation (Justified: Harris asserts that while physical processes correlate with consciousness, no analysis of these processes can logically yield a picture of consciousness, leaving an unbridgeable gap.)
Fundamental or emergent
Nagel’s Mind and CosmosPrimitive (or fundamental)
Sam HarrisMystery (Justified: Harris declines to fully endorse emergence, stating that while consciousness may be the lawful product of unconscious processing, he does not find that sentence meaningful in explaining sentience.)
Qualia
Nagel’s Mind and CosmosQualia (felt qualities) are the core of the problem, and Nagel argues that no objective or physicalist explanation currently formulated can account for their subjective reality.
Sam HarrisQualia (what it is 'like something' to be) are the phenomenon that physical events are 'mute' about, thus creating the unbridgeable mystery.
How it works
Mechanism
Nagel’s Mind and CosmosPrimarily focuses on exposing the conceptual limits of physical reductionism rather than positing a definitive mechanism. Mechanistically, his solution suggests consciousness arises through the composition of fundamental, panpsychic-like elements.
Sam HarrisNone (Justified: The core premise is the failure of all current and foreseeable physical/mechanistic principles to explain subjectivity.)
Where it is
Nagel’s Mind and CosmosUniversal/Systemic (inferred from universal monism/panpsychism leanings) or inherent in the fabric of nature.
Sam HarrisUnknown/Mysterious (Justified: While consciousness correlates with the brain, the theory explicitly rejects confining the explanation of consciousness to physical location or distribution because the physical world yields no evidence of consciousness.)
What it does
Nagel’s Mind and CosmosPrimarily critical, arguing against the materialist view that consciousness is an inert epiphenomenon. If mind is a fundamental principle, it implies an irreducible, organizing role in the cosmos.
Sam HarrisUnknown/Irreducible (Justified: Causal power is not explained by unconscious complexity. The presence of sentience is an ultimate mystery rather than a functional adaptation that can be described reductively.)
Evidence and criticism
Testability
Nagel’s Mind and CosmosUncertain/Primarily Conceptual. The theory's strength lies in its diagnosis of the explanatory gap, not in empirical verification. His suggested alternative (panpsychism) is highly speculative.
Sam HarrisConceptually Untestable (Justified: If the gap is unbridgeable, as Harris claims, the mystery cannot be dispelled by empirical science as currently practiced.)
Tests so far
Nagel’s Mind and CosmosNot stated
Sam HarrisNone (Justified: The framework is a diagnosis of science's failure to address the hard problem and does not propose empirical tests for the mystery itself.)
Criticisms
Nagel’s Mind and CosmosCriticized for retreating to 'mysterianism' and for rejecting established scientific frameworks (Neo-Darwinian materialism) without offering a concrete, robust, and detailed secular ontology as an alternative.
Sam HarrisIt functions primarily as a critique against reductionism and scientific optimism regarding consciousness, classifying the issue as an ultimate mystery, which reductionists reject as pessimism (mysterianism).
Sources
Key sources
Nagel’s Mind and Cosmos
- What Is It Like to Be a Bat? (1974)
- The View from Nowhere (1986)
- Mind & Cosmos: Why the Materialist Neo-Darwinian Conception of Nature Is Almost Certainly False (2012)
Sam Harris
- The mystery of consciousness (Part I & II), Sam Harris (2011)
- Explorations in Consciousness: Death Psychedelics and Mystical Experience (2023)