Head to head
Descartes’s Substance Dualism vs Russellian Monism
Descartes’s Substance Dualism and Russellian Monism, compared field by field from their entries in the Atlas.
At a glance
- Descartes’s Substance Dualism belongs to the Dualism family in Kuhn's Landscape of Consciousness, Russellian Monism to Neutral Monism.
- Both treat consciousness as fundamental.
- On AI consciousness, Descartes’s Substance Dualism says “No” and Russellian Monism says “Likely”.
- On life after death, Descartes’s Substance Dualism says “Yes” and Russellian Monism says “Conditional”.
- On mind uploading, Descartes’s Substance Dualism says “No” and Russellian Monism says “Likely”.
- On meaning and purpose, Descartes’s Substance Dualism says “Cosmic/Ultimate” and Russellian Monism says “Uncertain”.
Add more theories to this comparisonCompare other theories
The claim
In brief
Descartes’s Substance DualismRené Descartes holds that consciousness, which he calls thought (cogitatio), is the essence of an immaterial thinking substance (res cogitans) wholly distinct from extended, mechanical body (res extensa). Every conscious state, from reasoning and willing to pain, color, and emotion, is a mode of the thinking thing and is immediately present to it. Sensations and passions, though, arise only in the union of mind and body, where brain processes stand in regular relations to experiences they do not resemble.
Russellian MonismRussellian Monism posits that the physical world, described by physics only in terms of structure and relations, has an intrinsic nature (quiddities) that is phenomenal or proto-phenomenal. This approach integrates consciousness into the fundamental reality while avoiding the traditional problems of dualism and reductive materialism.
What consciousness is
Descartes’s Substance DualismConsciousness is thought, defined as everything that happens within us insofar as we are immediately conscious of it, and it is the principal attribute of the mind.
Russellian MonismConsciousness (or proto-consciousness) is the intrinsic, categorical nature or property ('quiddities' or 'inscrutables') underlying the relational structure of physical reality described by physics.
Big questions
Can AI be conscious?Differ
Descartes’s Substance DualismNoSince thought belongs only to immaterial substance and matter is pure extension, a machine, however complex, would be mechanism without a mind.
Russellian MonismLikelyIf consciousness is intrinsic to matter/energy, and the combination problem can be technologically harnessed, then artificial systems built from physical substrates should achieve consciousness.
Descartes’s Substance DualismYesDescartes presented the real distinction of soul and body as what makes the soul’s survival intelligible, and the Meditations announce that aim in their subtitle.
Russellian MonismConditionalSurvival is unlikely for the individual conscious aggregate unless the combination mechanism is preserved or the theory aligns with a cosmic monist view, as individual consciousness (the macroscopic combination) would likely dissolve upon biological death.
Descartes’s Substance DualismNoCopying the body’s mechanism would not copy the immaterial thinking substance.
Russellian MonismLikelyA single-stuff reality should permit virtual immortality, provided advanced technology can manipulate and harness the micropsychic properties to accurately reproduce the macroscopic conscious aggregate digitally.
Descartes’s Substance DualismCosmic/UltimateDescartes’s system rests on a non-deceiving God who guarantees knowledge and created even the eternal truths.
Russellian MonismUncertainMonisms generally allow for ultimate meaning/purpose/value. If RM takes a priority monist form with evolving consciousness, cosmic purpose may be implied.
Nature of mind
Ontology
Descartes’s Substance DualismSubstance dualism (Cartesian)
Russellian MonismNeutral Monism or Physical Monism or Phenomenal Monism (variant dependent); fundamentally Monistic.
Mind and body
Descartes’s Substance DualismMind and body are really distinct finite substances with exclusive essences, thought and extension, and could by divine power exist apart. They are joined in the human being, where bodily motions give rise to sensations and the mind moves the body, though Descartes never explained that interaction satisfactorily.
Russellian MonismMind and physical world are deeply intertwined, with mental properties constituting the intrinsic nature of fundamental physical entities (the categorical bases of physical dispositions).
Fundamental or emergent
Descartes’s Substance DualismPrimitive
Russellian MonismPrimitive (at the fundamental level of reality, as phenomenal or proto-phenomenal properties of micro-entities).
Qualia
Descartes’s Substance DualismSensory qualities are not properties of matter, which has only size, shape, motion, and arrangement. Experienced redness or pain is a mental mode arising in the embodied union and cannot be captured by extension.
Russellian MonismQualia correspond to the phenomenal properties (or their precursors) that constitute the intrinsic nature of fundamental matter.
How it works
Mechanism
Descartes’s Substance DualismMechanism on the bodily side and non-reduction on the mental side. Light mechanically affects eyes, nerves, and brain, and the mind then experiences color, distance, and shape in regular correspondence with those motions.
Russellian MonismThe key principle is the existence of unobserved, intrinsic categorical properties ('quiddities') of matter that are phenomenal, thereby grounding consciousness in fundamental reality without expanding the physical ontology of relations.
Where it is
Descartes’s Substance DualismThe mind is unextended. Sensations and passions are felt as belonging to one’s own body, and Descartes located mind-brain communication in the pineal gland.
Russellian MonismLocated in the intrinsic properties of fundamental micro-level physical entities or potentially instantiated by the universe as a whole (priority monism).
What it does
Descartes’s Substance DualismPassions are caused and strengthened by movements of the animal spirits and dispose the soul toward volition and action. The will can in turn move the body.
Russellian MonismAvoids the causal exclusion problem of dualism by embedding consciousness into the fundamental properties of the physical world, meaning consciousness underlies physical reality itself.
Evidence and criticism
Testability
Descartes’s Substance DualismConceptually testable
Russellian MonismSpeculative/Conceptual. Its fundamental claims regarding intrinsic properties are generally beyond empirical access or mathematical modeling.
Tests so far
Descartes’s Substance DualismNot stated
Russellian MonismNot stated
Criticisms
Descartes’s Substance DualismPrincess Elisabeth of Bohemia asked how an immaterial soul could move a material body, and the interaction problem remains unresolved. Arnauld and later critics charged circularity, since the proofs of God that guarantee clear and distinct perception themselves rely on clear and distinct perception. The standard reading denies consciousness to animals, which most now find implausible.
Russellian MonismThe primary challenge is the combination problem, which is critical: explaining how microphysical properties combine to form complex, integrated macro-level consciousness. If Panprotopsychism is assumed, it faces the problem of deriving consciousness (qualia) from proto-phenomenal properties.
Sources
Key sources
Descartes’s Substance Dualism
- Meditations on First Philosophy, René Descartes (trans. J. Cottingham, R. Stoothoff, and D. Murdoch) (1984)
- Principles of Philosophy, René Descartes (trans. J. Cottingham, R. Stoothoff, and D. Murdoch) (1985)
- The Passions of the Soul, René Descartes (trans. J. Cottingham, R. Stoothoff, and D. Murdoch) (1985)
Russellian Monism
- What is Russellian Monism?, T. Alter and Y. Nagasawa (2012)
- Russellian Monism, T. Alter and D. Pereboom (2019)
- Panpsychism and Panprotopsychism, D. Chalmers (2016)
More comparisons
Descartes’s Substance Dualism vs …
- Descartes’s Substance Dualism vs Orch OR
- Descartes’s Substance Dualism vs Spira’s Non-Duality
- Descartes’s Substance Dualism vs Goff’s Panpsychism
- Descartes’s Substance Dualism vs Bentley Hart’s Monism
- Descartes’s Substance Dualism vs Kastrup’s Analytic Idealism
- Descartes’s Substance Dualism vs Christian Soul Theory