Wayne Wright's 'Explanation and the Hard Problem' (2007) argued that the hard problem of consciousness, understood as the demand for an explanation whose link to phenomenal consciousness is epistemically transparent — one that yields a subjective sense of understanding — is scientifically irrelevant and hence 'extrascientific': the sense of understanding is neither necessary nor sufficient for satisfactory scientific explanation. The verdict rests on a manipulation-based, tool-oriented characterization of scientific explanation, and Wright himself left open what remains: whether consciousness science can achieve a full control (manipulation-based) explanation of phenomenal consciousness despite its methodological obstacles, and whether alternative accounts of scientific explanation would reinstate the hard problem as a genuine scientific problem.

Background

Phenomenal consciousness is the subjective, qualitative character of experience — the way things seem from the inside, as in the redness of a visual experience or the painfulness of pain. The 'hard problem of consciousness' (Chalmers 1995) is the problem of explaining why and how physical processes give rise to phenomenal consciousness at all, as opposed to the 'easy problems' of explaining cognitive functions such as attention, verbal report, and behavioral control. Levine (1983) named the residual dissatisfaction with any physical story the 'explanatory gap': even a complete functional and neural account seems to leave unexplained why the accompanying experience is as it is.

Wright (2007) analyzed what explanatory demand is embedded in this problem. On his reading, the demand is governed by an intelligibility requirement (IR): a satisfactory explanation of phenomenal consciousness must make the connection between physical processes and experience epistemically transparent, so that one can 'see why' the phenomenon follows — thereby producing a sense of understanding, the felt 'now I see why it must be so' (Trout 2002). Wright argued this demand is scientifically irrelevant. The sense of understanding is not a necessary condition on scientific explanation, because sciences that study complex systems routinely explain by identifying relationships that support prediction, intervention, and counterfactual reasoning — for example through mechanistic and manipulation-based accounts of explanation in the sense of Woodward (2003), on which to explain a phenomenon is to identify the changes one could make to a system that would change the phenomenon (an explanation in this interventionist sense is what Wright calls a control explanation) — and through multivariate statistical tools that extract hidden structure from data without any subjective 'seeing' of the connection. And the sense of understanding is not a sufficient condition, because empirical psychology shows that feeling is unreliable: hindsight bias, overconfidence bias, and confirmation bias can generate strong feelings of understanding for false accounts. Wright concluded that the hard problem, as standardly formulated, is an extrascientific matter — not a demand that the science of consciousness must meet — while acknowledging two qualifications that define this problem. First, his argument rests on a particular (manipulation-based, tool-oriented) characterization of scientific explanation; whether a defensible alternative account of explanation would make the intelligibility requirement a genuine scientific standard — thereby reinstating the hard problem as a scientific problem — is left open. Second, there remains a scientific hard problem of consciousness: the genuinely difficult methodological obstacles confronting the empirical study of consciousness, namely the impossibility of directly observing anyone else's conscious states, the fallibility of introspection and self-report, the limitations of current neuroscientific measurement, and divergent standards across allied fields; whether these can be overcome, and whether a full control explanation of phenomenal consciousness can be achieved, is left open. Wright also endorsed the proposal of Robbins and Jack (2006) that there is a psychological antagonism between the phenomenal stance (treating a creature as a subject of experience) and the physical stance (treating it as a physical system to be predicted and manipulated), leaving open whether future research can reduce this tension.

Later work has organized around these same questions. In the philosophy of science, a live debate concerns whether understanding, or its felt sense, is constitutive of explanation (Trout 2002 against; de Regt 2017 and Khalifa 2017 developing accounts on which understanding is tightly tied to explanation). In consciousness science, the methodological obstacles have become a research program in their own right: whether phenomenal consciousness can be studied empirically at all given its entanglement with report and access (Phillips 2018), whether consciousness-detection procedures can be calibrated against truth (Michel 2023), whether natural-kind reasoning offers a theory-neutral alternative to theory testing (McKilliam 2025), and whether interventionist experimentation can be pushed to the level of experience itself (Klein and Barron 2020).

Problem Statement

Determine the scientific status of the explanatory demand at the heart of the hard problem of consciousness, as posed by Wright (2007). The overarching objective is to establish what, if anything, the science of consciousness can and must deliver toward explaining phenomenal consciousness. This requires jointly answering two linked questions.

(1) The explanatory-standards question. Is the intelligibility requirement — the demand that an explanation of phenomenal consciousness make its link to physical processes epistemically transparent and yield a subjective sense of understanding — a genuine condition of explanatory adequacy on any defensible account of scientific explanation? Wright's negative verdict rests on a manipulation-based, tool-oriented characterization of explanation (Woodward 2003), under which explanations are judged by their support for prediction, intervention, and counterfactual reasoning rather than by felt transparency. A complete answer must engage the main rival accounts — such as Hempelian inferentialism (explanation as logical derivation of the phenomenon from laws and initial conditions), causal-mechanical and mechanistic accounts (explanation as exhibiting the mechanism that produces the phenomenon), unificationist accounts (explanation as unifying many phenomena under few patterns), pragmatic accounts (explanation as answering a why-question relative to a context of interests), and contemporary theories of scientific understanding (e.g., Trout 2002; de Regt 2017; Khalifa 2017) — and show either that no defensible account makes intelligibility a scientific demand for consciousness, upholding Wright's extrascientific verdict, or that some defensible account does, reinstating the hard problem as a scientific problem; and it must say which account (if any) carries the verdict and why the remaining accounts fail.

(2) The achievability question. Can consciousness science achieve a full control explanation of phenomenal consciousness — a manipulation-based explanation supporting systematic intervention on, and counterfactual reasoning about, conscious states — despite the methodological obstacles Wright identified: the impossibility of directly observing anyone else's conscious states, the fallibility of introspection and self-report, the limitations of current neuroscientific measurement, and divergent standards across allied fields? An answer must assess whether these obstacles are individually and jointly surmountable, and must state what a complete control explanation of phenomenal consciousness would have to deliver.

An answer that settles only one of the two questions is incomplete: the standards question fixes what science owes, and the achievability question fixes what science can deliver; together they determine the scientific status of the hard problem's explanatory demand. The associated open issues that Wright's concluding discussion also raises — whether the psychological antagonism between the phenomenal and physical stances can be reduced, and what criteria should govern the intellectually motivated pursuit of a sense of understanding — are neighboring questions and are not required for completion of this problem.

References

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