McLaughlin's Neurobiologicalism

Philosopher Brian P. McLaughlin’s neurobiologicalism is an a posteriori type-identity theory of phenomenal consciousness: for every type of phenomenal state or subjective experience, there is some type of neurobiological state with which it is numerically identical. McLaughlin combines unusually strong phenomenal realism with equally strong physicalism—pain, color experience, bodily sensations, imagery, emotions, and moods genuinely have subjective phenomenal character, yet these experiential types are not produced by, constituted by, or merely correlated with neural types; they are neurobiological types (McLaughlin, 2003, 2010, 2012, 2017). Crucially, he accepts a genuine conceptual and reductive-explanatory gap between phenomenal and neuroscientific concepts while denying that this entails any ontological gap, making his theory a sophisticated contemporary development of classical mind-brain identity theory rather than a denial of the hard problem.

In other words, Brian McLaughlin's neurobiologicalism is a type materialism specifically about phenomenal consciousness. Two commitments distinguish it within the identity-theoretic family. The identities are determinate—there is a fact about which neurobiological type each phenomenal type is, even if inquiry has not found it—which sets the view against deflationary formulations on which phenomenal concepts are too vague to pick out any particular correlate. And the explanatory gap is granted as a genuine epistemic phenomenon rather than dissolved as confusion, with McLaughlin supplying a positive account of why creatures with concepts like ours should feel it. Justification is abductive: the identities are inferred as the best explanation of lawlike psychoneural correlation, not derived a priori from physical description.

Phenomenal Realism and Neurobiological Identity

McLaughlin begins with phenomenal consciousness in the strongest ordinary sense: states for which there is something it is like for the subject to undergo them. Paradigms include feeling pain, seeing red, hearing a sound, experiencing an itch or hunger pang, entertaining sensory imagery, feeling fear or joy, and undergoing moods. Against strong illusionism, he regards the existence of such subjective experiences as secure; what requires explanation is their place in nature (McLaughlin, 2003, 2017).

His proposed answer is “neurobiologicalism”: for any phenomenal state type C, there is a neurobiological state type N such that C = N, where N is a state recognized by current neurobiology or a recognizable scientific successor to it (McLaughlin, 2012). The identity is stronger than supervenience, realization, constitution, or causal dependence. If pain is N, the phenomenal state and neural state are not two entities joined by a psychophysical relation. They are one state conceptualized in two radically different ways.

The Explanatory Gap Without an Ontological Gap

McLaughlin’s distinctive move is to concede much of Joseph Levine’s diagnosis of the explanatory gap. Phenomenal concepts—for example, the concept of the felt quality of pain—and neuroscientific concepts have virtually no a priori conceptual connections. No conceptual analysis of pain yields a description in the vocabulary of neuroscience, and no neuroscientific description logically generates the phenomenal concept simply by reflection (Levine, 1983; McLaughlin, 2010, 2012). McLaughlin consequently accepts that the familiar sort of reductive explanation that derives phenomenal truths through an a priori functional or conceptual analysis is unavailable.

What he rejects is the inference from conceptual difference to ontological difference. Two concepts can lack a priori connections while referring to one and the same property or state. Phenomenal concepts and neuroscientific concepts occupy profoundly different cognitive and epistemic roles: the former can be deployed through first-person attention to experience, whereas the latter arise within theoretical neuroscience. Their conceptual separation can therefore persist even if the states they designate are identical. McLaughlin thus accepts an enduring epistemic explanatory gap but denies a metaphysical explanatory gap (McLaughlin, 2010, 2012).

Neurobiologicalism: The Determinate Thesis

McLaughlin frames the position as an answer to a placement question—what is the place of phenomenal consciousness in nature?—and answers that phenomenal consciousness is neurobiological in nature, the most reasonable of the extant views all things considered (McLaughlin, 2012). Three restrictions give the thesis content. It is type-type rather than token, since token physicalism is compatible with there being no systematic phenomenal-physical mapping, and the systematic mapping is precisely what he takes to require explanation. It is restricted to phenomenal consciousness rather than extended to the mental generally. And the identified physical types are neurobiological—not functional, not computational, not physical in the abstract.

The determinacy marks the sharpest disagreement among contemporary identity theorists. Deflationary a posteriori physicalists argue that nothing in the semantic constitution of phenomenal concepts fixes which of a plurality of correlated material properties they refer to, so the search for the material essence of pain is chimerical and science will deliver only a range of correlates. Neurobiologicalism asserts what that view denies: there is a type of neurobiological state that pain is, and the obstacle to identifying it is contingent rather than semantic. Two theorists can therefore agree that consciousness is neurobiological, agree the identities are known abductively, and still disagree about whether there is anything determinate to be known.

The Abductive Route from Correlation to Identity

The argument begins from what McLaughlin calls the Correlation Thesis: for every type of sensation state there is a type of physical or functional state such that it is nomologically necessary that a being is in the one if and only if it is in the other (McLaughlin, 2001). He is emphatic that this settles nothing, being compatible with materialism and functionalism but equally with Cartesian dualism, dual-aspect theory, neutral monism, and panpsychism. Every one of these accommodates perfect lawlike covariation.

The point is made by asking what explains it. McLaughlin's answer is the Type Identity Thesis, and the reasoning is comparative. Identity explains the nomological necessity by eliminating the explanandum—not two items reliably co-occurring but one picked out two ways, and nothing comes apart from itself. Every rival must either accept the correlation as brute or introduce fundamental psychophysical laws, Feigl's nomological danglers, added to the world's inventory to underwrite the very regularity they were posited to explain. This makes the case for physicalism continuous with theoretical identification elsewhere in science. The route is shared with other contemporary defenders of the identity theory; what McLaughlin adds is that its terminus is neurobiologically specific.

Why the Explanatory Gap Is Real but Not Ontological

Levine's explanatory gap—the absence of any satisfying account of why a given neural state should feel as it does—is granted rather than disputed (Levine, 1983). What McLaughlin denies is the inference from an epistemic gap to an ontological one, placing him in what Chalmers labels type-B materialism: the identities are metaphysically necessary but knowable only a posteriori, with no a priori conditional connecting physical and phenomenal descriptions (Chalmers, 1996, 2003).

This is a substantive difference in attitude, not merely emphasis. One familiar physicalist strategy treats the sense of a gap as a residue of dualist habits that would evaporate under sufficiently thorough physicalist conviction—on which reading there was never a problem to solve. McLaughlin instead treats the gap as a real feature of our epistemic situation, generated by the structure of the concepts we deploy, persisting for any thinker equipped with phenomenal concepts however secure their physicalism. The gap is explained rather than explained away.

Phenomenal Concepts and the Failure of Conceivability

The explanation lies in the concepts. Phenomenal concepts are recognitional and imaginative rather than descriptive or inferential, and they remain conceptually independent of neurobiological concepts even when both pick out one property. That independence suffices to generate the felt gap, and it is what one should expect if the identities hold. McLaughlin defended this line under the heading of new wave materialism against the objection that appeal to phenomenal concepts collapses into dualism (Horgan & Tienson, 2001; McLaughlin, 2001).

The application to Kripke and Chalmers is the joint paper with Hill (Hill & McLaughlin, 1999). Kripke held that the standard materialist move—explaining apparent contingency by distinguishing a thing from its mode of presentation—is unavailable for pain, since feeling like pain is constitutive rather than a mode of presentation. Hill and McLaughlin respond that the appearance of contingency is produced by the faculty through which phenomenal states are imagined, whose deliverances are independent of the physical concepts in play, so imaginability is not a guide to possibility here. Zombie and inverted-spectrum intuitions become predictions of the theory rather than evidence against it. McLaughlin has separately argued that type materialism can accommodate a representational account of awareness of perceptual qualia, so the position does not depend on a particular theory of introspection (McLaughlin, 2016).

Emergence, Multiple Realization, and Machine Consciousness

According to McLaughlin, neurobiologicalism sits within a broader body of work on how higher-level properties relate to lower-level ones. His history of British emergentism argues that the doctrine collapsed not through philosophical refutation but through empirical displacement: quantum-mechanical explanation of chemical bonding removed the scientific motivation for configurational forces and emergent chemical properties (McLaughlin, 1992, 1997). The precedent generalizes—claims of irreducibility have historically dissolved as the underlying science matured—and supports an abductive, inference-to-the-best-explanation posture toward psychoneural identity.

The substrate restriction carries a consequence functionalism lacks. If phenomenal types are neurobiological types, a system duplicating human functional organization in silicon lacks phenomenal consciousness, however complete the duplication; artificial consciousness turns on constitution, not organization. This is anthropocentric provincialism derided by functionalists, but it follows directly from McLaughlin’s neurobiologicalism. Block has contested it, disputing McLaughlin's handling of functional role and the case of an android such as Commander Data (Block, 2018).

Assessment

The explanatory gains are clear. The theory requires no fundamental psychophysical laws, treats the mind-body question as continuous with ordinary theoretical identification, makes phenomenal consciousness an empirically tractable target rather than a metaphysical anomaly, and converts anti-physicalist intuitions from data into explananda.

The objections track the structure of its arguments. The abduction is only as strong as the comparative claim, and Russellian monists and dual-aspect theorists contest it, holding that their views explain correlation equally well while additionally explaining why any gap arises. Horgan and Tienson (2001) press the dilemma that phenomenal concepts either reveal phenomenal states as they are, yielding dualism, or are derivative, yielding failure. The Correlation Thesis as stated ranges over physical or functional states, so the step to neurobiological identities in particular requires argument beyond the abduction that motivates identity. And the determinacy requirement is the view's weak link: asserting that there is a fact about which neurobiological type pain is, while conceding no current method isolates it, invites the charge that the thesis is unfalsifiable in practice. No observation yet distinguishes neurobiologicalism from a nonreductive correlation view.

Moreover, the required type-level identities depend on neuroscience revealing sufficiently robust phenomenal-neural type correspondences, whereas biological variability and multiple realization may complicate such mappings. More fundamentally, critics can grant numerical identity yet argue that it leaves untouched the central phenomenological demand: why does the identical neural state have this particular felt character? McLaughlin’s response is deliberately revisionary—the demand for a further causal explanation misconstrues identity, although a conceptual explanatory gap remains. Whether that dissolves the hard problem ontologically or restates its deepest feature is the central node of contention. His neurobiologicalism is therefore less a mechanistic theory of how brains generate consciousness than a metaphysical theory of what phenomenal consciousness ultimately is.

References

Block, N. (2018). Functional role, superficialism and Commander Data: Reply to Brian McLaughlin. In A. Pautz & D. Stoljar (Eds.), Blockheads! Essays on Ned Block's Philosophy of Mind and Consciousness. MIT Press.

Chalmers, D. J. (1996). The Conscious Mind: In Search of a Fundamental Theory. Oxford University Press.

Chalmers, D. J. (2003). The content and epistemology of phenomenal belief. In Q. Smith & A. Jokic (Eds.), Consciousness: New Philosophical Perspectives (pp. 220–272). Oxford University Press.

Hill, C. S., & McLaughlin, B. P. (1999). There are fewer things in reality than are dreamt of in Chalmers's philosophy. Philosophy and Phenomenological Research, 59(2), 445–454.

Horgan, T., & Tienson, J. (2001). Deconstructing new wave materialism. In C. Gillett & B. Loewer (Eds.), Physicalism and Its Discontents (pp. 307–318). Cambridge University Press.

Levine, J. (1983). Materialism and qualia: The explanatory gap. Pacific Philosophical Quarterly, 64, 354–361.

McLaughlin, B. P. (1992). The rise and fall of British emergentism. In A. Beckermann, H. Flohr & J. Kim (Eds.), Emergence or Reduction? Essays on the Prospects of Nonreductive Physicalism (pp. 49–93). De Gruyter.

McLaughlin, B. P. (1997). Emergence and supervenience. Intellectica, 25, 25–43.

McLaughlin, B. P. (2001). In defense of new wave materialism: A response to Horgan and Tienson. In C. Gillett & B. Loewer (Eds.), Physicalism and Its Discontents. Cambridge University Press.

McLaughlin, B. P. (2012). On justifying neurobiologicalism for consciousness. In S. Gozzano & C. S. Hill (Eds.), New Perspectives on Type Identity: The Mental and the Physical (pp. 207–229). Cambridge University Press.

McLaughlin, B. P. (2016). Hill on phenomenal consciousness. Philosophical Studies, 173(3), 851–860.

McLaughlin, B. P. (2017). Type materialism for phenomenal consciousness. In S. Schneider & M. Velmans (Eds.), The Blackwell Companion to Consciousness (pp. 415–429). Wiley.