Head to head
Epiphenomenalism vs Sam Harris
Epiphenomenalism Theory and S. Harris’s Mystery of Consciousness, compared field by field from their entries in the Atlas.
At a glance
- Epiphenomenalism belongs to the Dualism family in Kuhn's Landscape of Consciousness, Sam Harris to Challenge.
- They give the same kind of answer on life after death and meaning and purpose.
- On AI consciousness, Epiphenomenalism says “Likely” and Sam Harris says “No”.
- On mind uploading, Epiphenomenalism says “Likely” and Sam Harris says “No”.
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The claim
In brief
EpiphenomenalismThis theory posits that consciousness is a non-reducible product of the biological brain, but mental states have absolutely no causal power over physical reality. Our subjective awareness is real, yet our perception that our thoughts cause actions is mistaken, as consciousness is entirely inert, like foam on an ocean wave.
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
EpiphenomenalismConsciousness is identified as phenomenal properties that are ontologically distinct from physical properties but are causally dependent on them (Physical → Phenomenal).
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
EpiphenomenalismLikelyIf consciousness is merely a non-causal byproduct (foam) of physical processes in the brain , replicating those physical processes in AI should produce the same conscious states without the non-causal mental states hindering functional replication.
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.
Does consciousness survive death?Both agree
EpiphenomenalismNoConsciousness is entirely physical and solely the product of biological brains. This physical dependence precludes survival beyond bodily death.
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.
EpiphenomenalismLikelyThe inert nature of consciousness means that uploading the physical states would necessarily duplicate the epiphenomenal mental states. The inert 'foam' should have little impact on achieving virtual immortality.
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.
Does it give life meaning?Both agree
EpiphenomenalismHumanistic onlyAs a philosophical materialism theory, it provides no ultimate meaning or purpose. Since consciousness is causally inert, it cannot confer cosmic teleological 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
EpiphenomenalismWeak form of Dualism or Non-Reductive Physicalism. It affirms the complete causal closure of the physical.
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
EpiphenomenalismMental states are entirely the product of biological brains. Physical states cause phenomenal states, but phenomenal states have no causal effect on the physical (one-directional causation).
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
EpiphenomenalismEmergent. Consciousness is solely the product of biological brains.
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
EpiphenomenalismPhenomenal properties (qualia) are real and ontologically distinct from physical properties , but they are epiphenomena and thus causally inert.
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
EpiphenomenalismThe principle of the 'causal closure of the physical' dictates that mental states, whatever their nature, must be entirely inert byproducts.
Sam HarrisNone (Justified: The core premise is the failure of all current and foreseeable physical/mechanistic principles to explain subjectivity.)
Where it is
EpiphenomenalismEntirely located in the physical, biological brain.
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
EpiphenomenalismMental states have no causal powers. The mind is entirely inert and there is no 'top-down causation'; consciousness is a non-functional byproduct.
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
EpiphenomenalismConceptually challenged. Its primary claim—that conscious states lack causal force—is counterintuitive and difficult to test empirically, as it involves proving a negative causal link.
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
EpiphenomenalismNot 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
EpiphenomenalismThe theory is counterintuitive because it strongly seems to us that our phenomenally conscious states causally matter. It forces the acceptance that our sense of mental causation (thoughts causing things) is a 'kind of illusion or trick'.
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
Epiphenomenalism
- Consciousness (2019)
- Facing up to the Problem of Consciousness (1995)
- What Is Consciousness? (Little Debates about Big Questions), A. Kind and D. Stoljar (2023)
Sam Harris
- The mystery of consciousness (Part I & II), Sam Harris (2011)
- Explorations in Consciousness: Death Psychedelics and Mystical Experience (2023)