Friedrich August von Hayek, What Is Mind?

Hayek’s What Is Mind?, presented here in its 2017 English translation, is a lecture on the mind–body problem that connects physiological psychology with the methodology of the social sciences. Its movement is from reformulating the problem, through a sketch of neural classification, to the philosophical consequences and limits of explanation. Hayek rejects the search for an intrinsic mental substance: what requires explanation is an order of relationships. His central claim is that physical processes can generate the structure we experience as mind, although the human mind cannot fully explain its own operations. Naturalism thus leads, unexpectedly, to limits on reduction and prediction.

The opening argument distinguishes two ways of organizing the same world. Memories, images, and hallucinations initially allow us to distinguish mental experience from currently present objects. Cross-checking one sense against others then supplies an elementary test of reality. Scientific experiment extends this procedure: apparently identical objects may behave differently, while apparently different objects may exhibit identical relationships. Physics progressively replaces classification by sensory appearance with classification by interactions.

At the same time that the system of sensory qualities disappears from physics, it becomes a problem in psychology.

This shift defines psychology’s task. Eliminating color, warmth, or sweetness from physical descriptions does not explain why the world appears through those qualities. Hayek’s comparison between the linear sequence of light wavelengths and the circular relationships among perceived colors illustrates the discrepancy. Mental and physical descriptions concern the same events, but locate them within differently organized systems. Explaining mind therefore means accounting for the sensory order, rather than discovering a second substance behind it.

Hayek’s decisive move is to define mental qualities relationally. A sensation’s character consists in the differences its occurrence makes to other mental processes and to behavior under different circumstances. He contends that explaining these differences would exhaust what needs explanation. This is a substantive theoretical commitment: it treats causal relationships, rather than an isolated quality supposedly left over after their explanation, as the proper object of inquiry.

What I am asserting is that, if we succeed in demonstrating the presence of structural relationships in human organisms that are isomorphous with the structural relationships in the mental realm, we have gone as far as we can in “explaining” the mental realm.

Structural equivalence supplies the proposed bridge between the two orders. Physical elements need not possess sensory qualities individually; their connections must reproduce the relevant relations among mental events. The central nervous system offers a possible mechanism. Connections formed between simultaneously active nerve cells allow later impulses to activate linked cells. Hayek interprets this apparatus as a classifier: impulses acquire equivalent or different significance through their effects within the network. Overlapping connections permit membership in multiple classes, classification of groups, and successive classes of classes. Concepts and perceived configurations consequently extend the same operation already responsible for sensation.

The account reverses the familiar sequence in which experience assembles elementary sensations into complex representations.

If my view is correct, however, there is no such thing as simple and pure sensation that can be attributed to the stimulation of specific nerves.

Sensory qualities arise only after impulses have entered a relational system. Physiological, pre-perceptive experience establishes the connections that make conscious experience possible. Hayek therefore retains the empiricist claim that knowledge comes from experience while rejecting consciously given sensations as its ultimate foundation. He invokes Kant’s categories as ordering principles acquired through earlier interaction with the world but subsequently presupposed by conscious perception. Such principles cannot themselves be tested through the experience they organize, although the system continues to change through new experience. Neither sensory appearance nor scientific classification is permanently fixed; phenomenalism cannot secure an unchanging descriptive foundation.

This relational conception also redirects the dispute over materialism. Hayek rejects substance dualism, arguing that treating mind as a special substance imports categories drawn from material things. Mind is instead an order manifested in relationships among material events. Its explanation depends on structure, not on whether the underlying processes are electrical, chemical, or realized in some other physical medium. He nevertheless presents the mechanism as an incomplete theoretical sketch, not a finished physiological demonstration.

The final section distinguishes explanation in principle from detailed explanation capable of predicting particular outcomes. For Hayek, the obstacle to complete self-explanation is not merely inadequate observation. A classification apparatus must possess greater complexity than the objects it exhaustively classifies; accordingly, a brain cannot fully classify its own functioning.

To explain the functioning of our brain or of our thinking, we would need a higher-order brain.

This asserted complexity limit preserves the possibility of explaining how mental order arises while denying that humans can derive particular thoughts and decisions completely from their physical conditions. Hayek leaves open whether a more powerful artificial brain might accomplish what humans cannot. His conclusion is therefore a limit on our explanatory capacities, not a denial of physical causation.

The lecture’s methodological significance lies in this combination of naturalistic explanation and practical dualism. Social inquiry must continue to begin with directly known mental experience, rather than replace it with descriptions of material processes. Hayek likewise separates determination in principle from our ability to identify the causes of particular decisions. His closing defense of freedom rests on the meaning of acting through one’s will, not on exemption from nature. The work makes classification both the mechanism of cognition and the source of cognition’s explanatory limits.