Open the map

Head to head

Crick and Koch’s NCC vs Searle’s Biological Naturalism

Crick and Koch’s Neural Correlates of Consciousness (NCC) and Searle’s Biological Naturalism, compared field by field from their entries in the Atlas.

At a glance

Add more theories to this comparisonCompare other theories

The claim

In brief
Crick and Koch’s NCCThis theory proposes a scientific agenda to identify the Neural Correlate of Consciousness (NCC), defined as the minimum activities in the brain that are jointly sufficient and necessary for any specific conscious perception or subjective experience. It asserts that consciousness is entirely physical and can be fully reduced to these specific brain activities.
Searle’s Biological NaturalismBiological Naturalism posits that consciousness is a real, irreducible, subjective biological feature of the brain, entirely caused by lower-level neurobiological processes and realized as higher-level system features. This approach seeks to solve the mind-body problem by accepting the scientific worldview while acknowledging the first-person ontology of conscious experience.
What consciousness is
Crick and Koch’s NCCConsciousness (phenomenal consciousness/qualia) is identified as the Neural Correlate of Consciousness (NCC), the precise minimum pattern of neural activity in the brain necessary and sufficient for subjective experience.
Searle’s Biological NaturalismConscious states are identified as real parts of the real world that are higher-level, system features of the brain, defined as states of awareness, sentience, or feeling that persist during wakefulness.

Big questions

Crick and Koch’s NCCYesIf consciousness is entirely reducible to physical organizational patterns (NCC), then non-biological systems capable of replicating those precise patterns should also become conscious, barring technological constraints.
Searle’s Biological NaturalismConditionalSearle rejects consciousness via simulation (Chinese Room Argument) but argues that if the causally sufficient biological mechanism is known, an artificial machine that implements that same mechanism could be conscious, as consciousness does not strictly require biological neurons, only sufficient causal power.
Crick and Koch’s NCCNoAs a Materialist theory, consciousness is wholly dependent on the physical brain; cessation of brain function entails the end of consciousness.
Searle’s Biological NaturalismNoConsciousness is entirely physical and solely the product of biological brains; therefore, death of the brain and body means irrevocable, permanent non-existence.
Crick and Koch’s NCCYesIf the NCC states can be perfectly measured and replicated in a digital or artificial medium (mind uploading), the resulting system would be functionally and phenomenally identical, achieving virtual immortality in principle.
Searle’s Biological NaturalismYesIf consciousness is entirely explainable by physical/biological states, then duplicating those states (and their causal relations) in a non-biological medium would, in principle, allow for the uploading and continuation of the first-person mental self.
Crick and Koch’s NCCHumanistic onlyConsistent with Materialism, consciousness is a biological product of evolution and physics, conferring no ultimate cosmic meaning or teleology beyond that which humans create for themselves.
Searle’s Biological NaturalismHumanistic onlyAs a materialist theory, Biological Naturalism struggles to rationalize ultimate cosmic meaning or purpose, though humanistic meaning created by ourselves remains possible.

Nature of mind

Ontology
Crick and Koch’s NCCReductive Physicalism/Materialism. The NCC approach is considered macroscopic materialism.
Searle’s Biological NaturalismPhysicalism (Biological Naturalism). It holds that consciousness is part of nature as a subjective, qualitative biological property, rejecting attempts to 'naturalize' it by denying its subjective ontology.
Mind and body
Crick and Koch’s NCCIdentity Theory. Mental states are wholly identical to and fully explained by the physical NCC states.
Searle’s Biological NaturalismConscious states are causally reduced to lower-level brain processes (causal reducibility), but are ontologically irreducible to these processes because consciousness has a subjective (first-person) ontology while its basis has an objective (third-person) ontology.
Fundamental or emergent
Crick and Koch’s NCCEmergent
Searle’s Biological NaturalismEmergent
Qualia
Crick and Koch’s NCCQualia (the qualitative feel of experience) are identified with the minimum neural activities (NCC) that are jointly sufficient for specific conscious perception, although the mechanism for this identity remains the central 'hard problem' challenge.
Searle’s Biological NaturalismConscious states are inherently qualitative, in the sense that there is a distinct qualitative feel to being in any particular conscious state, and this qualitative feel is a real and irreducible part of the world.

How it works

Mechanism
Crick and Koch’s NCCThe search for and definition of the Neural Correlate of Consciousness (NCC): the specific minimum neural activities necessary and sufficient for subjective experience.
Searle’s Biological NaturalismThe principle is that all conscious states are reliably and universally caused by lower-level brain processes and realized as system features, functioning as a real biological machine.
Where it is
Crick and Koch’s NCCLocalized in specific brain areas. Early candidates included the claustrum (as a 'conductor' coordinating percepts); later candidates focused on the posterior cerebral cortex (temporo-parietal-occipital hot zone).
Searle’s Biological NaturalismLocalized in the biological brain, specifically realized in the brain as higher-level or system features.
What it does
Crick and Koch’s NCCConsciousness is directly caused by, and is identical to, the NCC activity. NCC mechanisms (spikes, flows, circuits) are seen as constitutive of phenomenal consciousness.
Searle’s Biological NaturalismConscious states function causally (causal efficacy) as real parts of the real world, providing a basis for intentional action and interaction with the environment.

Evidence and criticism

Testability
Crick and Koch’s NCCEmpirically testable. The search for the NCC is defined as a scientific program seeking testable biological bases for consciousness.
Searle’s Biological NaturalismEmpirically testable in principle, as the theory requires finding the exact causal details of how lower-level brain processes cause consciousness.
Tests so far
Crick and Koch’s NCCIdentifying specific clusters of neurons or brain regions (like the claustrum or posterior cortex) that are active during conscious experience.,Measuring electrophysiological activity (e.g., action potentials and neural circuits).
Searle’s Biological NaturalismThe theory is generally supported by empirical evidence from neuroscience showing the link between consciousness and brain activity (e.g., brain impairment, brain stimulation).
Criticisms
Crick and Koch’s NCCThe primary tension is the 'explanatory gap': identifying a correlation (NCC) does not explain the identity statement of how physical activity (spikes/chemicals) literally generates phenomenal feel (qualia). The failure to identify a 'clear' NCC after decades of research is a practical limitation.
Searle’s Biological NaturalismCritics dispute the claim that the causal connection between brain states and consciousness is fully established. Tension exists in maintaining materialism while arguing consciousness is ontologically subjective and irreducible to objective physical processes.

Sources

Key sources
Crick and Koch’s NCC
  • Towards a neurobiological theory of consciousness, F. Crick and C. Koch (1990)
  • What is the function of the claustrum?, F. Crick and C. Koch (2005)
  • The Quest for Consciousness: a Neurobiological Approach, C. Koch (2004)
Searle’s Biological Naturalism
  • The Rediscovery of Mind (1992)
  • Biological naturalism (2007)
  • What things are conscious? (2007)

More comparisons

All head-to-head comparisons →