Head to head
Frankish’s Illusionism vs Higher-Order Thought Theory
Frankish’s Illusionism and Rosenthal’s Higher-Order Thought, compared field by field from their entries in the Atlas.
At a glance
- Both belong to the Materialism family in Kuhn's Landscape of Consciousness.
- Both treat consciousness as emergent.
- They give the same kind of answer on AI consciousness, life after death and meaning and purpose.
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The claim
In brief
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’.
Higher-Order Thought TheoryDavid Rosenthal holds that a mental state is conscious when its subject has a higher-order thought that he or she is in that state, a thought that need not itself be conscious and does not seem to rest on inference. Mental qualities such as the redness of a sensation exist whether or not they are conscious; Rosenthal explains them separately, by how they map the perceptible properties we can discriminate.
What consciousness is
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.
Higher-Order Thought TheoryA state’s being conscious consists in the subject being aware of it by way of a suitable higher-order thought that one is in that state.
Big questions
Can AI be conscious?Both agree
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.
Higher-Order Thought TheoryPossibleSince consciousness depends on having suitable higher-order thoughts about one’s own states, a system able to form such thoughts would meet the condition in principle.
Does consciousness survive death?Both agree
Frankish’s IllusionismNoSince conscious states are functional states of a living brain, they end when the brain stops functioning.
Higher-Order Thought TheoryNoConscious states are natural states of an organism, so nothing remains conscious once those states stop occurring.
Frankish’s IllusionismNo position
Higher-Order Thought TheoryPossibleIf the relevant first-order states and higher-order thoughts were reproduced, the view gives no principled reason the copy would lack consciousness.
Does it give life meaning?Both agree
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’.
Higher-Order Thought TheoryHumanistic onlyThe theory is a naturalistic account of mental states and carries no cosmic purpose.
Nature of mind
Ontology
Frankish’s IllusionismPhysicalism (strong illusionism)
Higher-Order Thought TheoryPhysicalism (naturalistic functionalism)
Mind and body
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.
Higher-Order Thought TheoryMental states, their qualities, and the higher-order thoughts that make them conscious are all natural states of the organism; Rosenthal expects neural correlates of consciousness to be whatever mechanism produces the higher-order awareness.
Fundamental or emergent
Frankish’s IllusionismEmergent
Higher-Order Thought TheoryEmergent
Qualia
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.
Higher-Order Thought TheoryMental qualities are fixed by their role in perceptual discrimination and occupy a ‘quality space’ that mirrors the similarities among perceptible properties. Because these qualities do not depend on consciousness, a sensation can have qualitative character without being conscious, as in subliminal perception.
How it works
Mechanism
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.
Higher-Order Thought TheoryA non-inferential higher-order thought that one is in a given state, which makes that first-order state conscious even when the thought itself is unconscious.
Where it is
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.
Higher-Order Thought TheoryNot stated
What it does
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.
Higher-Order Thought TheoryNot stated
Evidence and criticism
Testability
Frankish’s IllusionismConceptually testable
Higher-Order Thought TheoryConceptually testable
Tests so far
Frankish’s IllusionismFrankish holds that the reactive changes constituting experience are in principle experimentally detectable, which opens the experiences of other creatures to study.
Higher-Order Thought TheoryNot stated
Criticisms
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.
Higher-Order Thought TheoryFirst-order theorists argue that higher-order awareness is an unneeded extra ingredient, and deflationists say being aware of a conscious state is like ‘smiling a smile’. Rosenthal replies that a deflated awareness cannot explain the contrast between conscious and unconscious states.
Sources
Key sources
Frankish’s Illusionism
- Frankish’s Illusionism (Landscape of Consciousness), Keith Frankish (2021)
Higher-Order Thought Theory
- Rosenthal’s Higher-Order Thought, Landscape of Consciousness, David Rosenthal (2005)