Head to head
Epiphenomenalism vs Frankish’s Illusionism
Epiphenomenalism Theory and Frankish’s Illusionism, 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, Frankish’s Illusionism to Materialism.
- Both treat consciousness as emergent.
- They give the same kind of answer on life after death and meaning and purpose.
- On AI consciousness, Epiphenomenalism says “Likely” and Frankish’s Illusionism says “Possible”.
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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.
Frankish’s IllusionismKeith Frankish holds that conscious experiences are real but not what they seem: the irreducibly subjective ‘phenomenal properties’ or qualia we ascribe to them are an introspective illusion. Introspection builds a simplified, schematic model of the brain’s complex reactions to stimulation, and we mistake that model for direct awareness of inner qualities, so the hard problem gives way to an ‘illusion problem’.
What consciousness is
EpiphenomenalismConsciousness is identified as phenomenal properties that are ontologically distinct from physical properties but are causally dependent on them (Physical → Phenomenal).
Frankish’s IllusionismConscious states are complex functional states of the brain that sustain rich sensory engagement with the world and flexible control of behavior. Their distinctive features are functional, which Frankish calls quasi-phenomenal properties.
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.
Frankish’s IllusionismPossibleSince consciousness is a complex functional state, a system with the right reactive and sensory organization could have it, though Frankish does not address machines directly.
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.
Frankish’s IllusionismNoSince conscious states are functional states of a living brain, they end when the brain stops functioning.
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.
Frankish’s IllusionismNo position
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.
Frankish’s IllusionismHumanistic onlyFrankish grounds value in what creatures are motivated to seek or avoid and argues that illusionism widens ethical concern to other animals across a graded ‘consciousness space’.
Nature of mind
Ontology
EpiphenomenalismWeak form of Dualism or Non-Reductive Physicalism. It affirms the complete causal closure of the physical.
Frankish’s IllusionismPhysicalism (strong illusionism)
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).
Frankish’s IllusionismConscious experiences are physically realized functional states. Phenomenal properties are intentional objects, represented but never instantiated, like the impossible objects Nicholas Humphrey compares them to.
Fundamental or emergent
EpiphenomenalismEmergent. Consciousness is solely the product of biological brains.
Frankish’s IllusionismEmergent
Qualia
EpiphenomenalismPhenomenal properties (qualia) are real and ontologically distinct from physical properties , but they are epiphenomena and thus causally inert.
Frankish’s IllusionismQualia do not exist. Introspection misrepresents brain states, as perception misrepresents some features of the world, and introspective information bound to perception makes external things seem to carry vivid sensory qualities, such as an apple’s redness, that reflect their significance for us.
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.
Frankish’s IllusionismThe reactivity schema: introspective systems track the overall psychological impact of stimulation without representing its detail, and this simplified model is mistaken for direct acquaintance with qualities. Frankish borrows Daniel Dennett’s image of a computer’s user illusion, whose icons have no literal counterparts in the machine.
Where it is
EpiphenomenalismEntirely located in the physical, biological brain.
Frankish’s IllusionismDistributed across the brain. The subject of the illusion is the whole organism, and the work of registering and reacting to it is shared among many unconscious subsystems, with no Cartesian theater.
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.
Frankish’s IllusionismConscious states guide flexible, intelligent behavior. The illusion itself is made of physical representations and so has causal effects, which may be adaptive, as Nicholas Humphrey argues; this avoids the threat of epiphenomenalism.
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.
Frankish’s IllusionismConceptually testable
Tests so far
EpiphenomenalismNot stated
Frankish’s IllusionismFrankish holds that the reactive changes constituting experience are in principle experimentally detectable, which opens the experiences of other creatures to study.
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'.
Frankish’s IllusionismThe central objection, a version of Descartes’ cogito, holds that our own phenomenal states are indubitable data. Galen Strawson argues that illusionism denies the main source of ethical value. Others object that an illusion needs an audience.
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)
Frankish’s Illusionism
- Frankish’s Illusionism (Landscape of Consciousness), Keith Frankish (2021)