Head to head
Dennett’s Illusionism vs Higher-Order Thought Theory
Dennett’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
Dennett’s IllusionismDaniel Dennett argues that qualia, conceived as intrinsic, ineffable, private, and immediately known properties of experience, do not exist; they are philosophers’ inventions. Experience is real, but it is not what it seems from the inside: the brain’s unconscious processes produce a benign ‘user illusion’, and there is nothing to consciousness beyond the functions and dispositions involved.
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
Dennett’s IllusionismConsciousness is the functional activity of the brain, which presents itself to us as a user illusion. ‘There are no qualia.’
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
Dennett’s IllusionismPossibleSince consciousness is nothing beyond functions and dispositions, a machine with the right functional organization could have it; Dennett does not take this up here.
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
Dennett’s IllusionismNoSince consciousness is a product of the brain’s processes, it ends when they end.
Higher-Order Thought TheoryNoConscious states are natural states of an organism, so nothing remains conscious once those states stop occurring.
Dennett’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
Dennett’s IllusionismHumanistic onlyDennett’s materialism, and his place among the New Atheists, leave no room for cosmic purpose.
Higher-Order Thought TheoryHumanistic onlyThe theory is a naturalistic account of mental states and carries no cosmic purpose.
Nature of mind
Ontology
Dennett’s IllusionismPhysicalism (illusionist)
Higher-Order Thought TheoryPhysicalism (naturalistic functionalism)
Mind and body
Dennett’s IllusionismConsciousness is wholly a product of the brain’s unconscious processes. Dennett rejects any inner, non-physical domain of felt properties.
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
Dennett’s IllusionismEmergent
Higher-Order Thought TheoryEmergent
Qualia
Dennett’s IllusionismThere are no qualia in the traditional sense. Dennett calls the supposed intrinsic, ineffable, private properties ‘nothing but philosophers’ inventions’.
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
Dennett’s IllusionismThe user illusion. As a computer’s desktop icons stand in for complex underlying processes, the brain presents itself to us in a simplified form we mistake for an inner world of qualities.
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
Dennett’s IllusionismIn the brain’s unconscious processes, with no inner theater.
Higher-Order Thought TheoryNot stated
What it does
Dennett’s IllusionismThe user illusion is benign: it lets us manage ourselves without access to the brain’s underlying complexity.
Higher-Order Thought TheoryNot stated
Evidence and criticism
Testability
Dennett’s IllusionismConceptually testable
Higher-Order Thought TheoryConceptually testable
Tests so far
Dennett’s IllusionismNot stated
Higher-Order Thought TheoryNot stated
Criticisms
Dennett’s IllusionismDennett is often read as denying that experience exists, and critics reply that an illusion of experience would itself be an experience. Dennett resisted the eliminativist label, though many philosophers apply it to his rejection of qualia.
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
Dennett’s Illusionism
- Consciousness Explained, Daniel Dennett
- I've Been Thinking, Daniel Dennett (2023)
- Dennett’s Illusionism (Landscape of Consciousness), Daniel Dennett (1992)
Higher-Order Thought Theory
- Rosenthal’s Higher-Order Thought, Landscape of Consciousness, David Rosenthal (2005)