Locke’s Reflexive Consciousness and the Making of the Person

Philosopher John Locke’s theory of consciousness makes immediate self-awareness constitutive of thinking and makes the continuity of that consciousness—not identity of body or soul—the basis of personal identity. Phenomenal consciousness consists in the mind’s experienced ideas of sensation and reflection, each accompanied by an implicit awareness of oneself as undergoing it; extended backward through appropriative remembrance, this consciousness creates the temporally enduring person who owns actions, anticipates happiness and misery, and bears moral responsibility. Locke thereby helped establish the modern conception of consciousness as subjective, first-person, self-intimating, and central to personhood, while remaining strikingly agnostic about whether its underlying substance is material or immaterial.

In other words, Locke's theory of consciousness holds that consciousness is not a substance, a faculty, or a separate second thought, but a self-intimating feature internal to every perception of an idea: to perceive is unavoidably to perceive that one perceives (Locke, 1689/1975, II.xxvii.9). Phenomenal consciousness enters at the level of simple ideas—color, warmth, pain—which the mind receives passively and can neither manufacture nor decompose. Locke then severs personal identity from the identity of any underlying substance and relocates it in sameness of consciousness, while conceding that we cannot know whether thinking is superadded to organized matter or annexed to an immaterial soul. His account thus founds the modern psychological conception of the self and installs at its origin an explicit confession of ignorance about how any physical arrangement could yield experience—two moves that make Locke the hinge on which much subsequent Western argument about consciousness turns.

Consciousness as Inseparable from Thinking

Locke writes as "consciousness" was detaching from conscientia, the shared or moral knowledge of conscience, and he is among the principal agents of that separation (Jorgensen, 2025; Thiel, 2011; Balibar, 2013). His account arrives inside his definition of a person: a thinking intelligent being with reason and reflection, able to consider itself as itself in different times and places, which it does only by that consciousness "which is inseparable from thinking" (Locke, 1689/1975, II.xxvii.9). Consciousness is thus coextensive with thought—but Locke restricts the claim's reach. Against the Cartesians, he denies that the soul always thinks: "every drowsy nod shakes their doctrine" (Locke, 1689/1975, II.i.13). Thinking is an operation of the soul, not its essence, which detaches the persistence of a substance from the continuity of experience.

Consciousness as Reflexive Awareness

All ideas originate in experience, through sensation of external objects or reflection on the mind’s own operations—perceiving, thinking, doubting, believing, reasoning, knowing, willing, and desiring (Locke, 1689/1975). Consciousness, however, is not simply reflection. Locke defines it as “the perception of what passes in a man’s own mind” and insists that thinking consists in being conscious that one thinks. He therefore rejects the Cartesian-scholastic hypothesis that the soul continually thinks during dreamless sleep without the person knowing it: an entirely unnoticed thought is, for Locke, scarcely intelligible as thought.

The best interpretation is not that every first-order perception causes a separate introspective act. Rather, consciousness is an immediate, noninferential, self-referential awareness internal to occurrent perception: in seeing red, feeling pain, or entertaining a thought, the subject is tacitly aware of itself as seeing, feeling, or thinking (Coventry and Kriegel, 2008; Weinberg, 2016). Locke thus anticipates reflexive or self-representational theories more closely than standard higher-order perception theories. Modern higher-order theories distinguish conscious from unconscious mental states by adding a representation of the first-order state; Locke generally denies the relevant unconscious first-order mentality and treats awareness as intrinsic to thinking itself.

Phenomenal Contents and the Experienced World

Locke’s “ideas” are the immediate objects of perception, encompassing sensory qualities, bodily sensations, pleasures and pains, emotions, memories, imaginings, and acts of thought. Simple ideas are passively received; the mind then compares, combines, abstracts, and relates them. His primary-secondary quality distinction is especially important phenomenally. Solidity, extension, figure, motion, rest, and number resemble features in bodies, whereas colors, sounds, tastes, smells, warmth, and similar qualities are ideas produced in perceivers by powers of bodies and need not resemble their physical causes (Locke, 1689/1975).

This separates qualitative appearance from external microphysical structure: the blueness experienced in seeing a violet belongs to the idea in consciousness, while the flower possesses a power—grounded, Locke supposes, in corpuscular organization—to produce that experience. He therefore gives a proto-scientific account of why experience presents qualities not literally instantiated in objects as experienced. Yet he does not explain why corpuscular motions should generate any qualitative feeling at all. Locke identifies the causal and epistemic architecture of experience, not a solution to the much-later “hard problem”; indeed, his admission that we do not know wherein thinking consists marks early appreciation of the depth of the explanatory gap (Chalmers, 1995).

Self, Personhood, and Temporal Identity

Locke distinguishes the human organism, the thinking substance or soul, and the person. A person is “a thinking intelligent Being” capable of reason and reflection and able to consider itself as itself across different times and places (Locke, 1689/1975). Present consciousness makes one a self to oneself; because every sensation or thought includes awareness of one’s own activity, each person has intuitive certainty of its present existence. But personhood over time requires consciousness to reach backward and appropriate past experiences and actions as one’s own.

Locke’s account is consequently broader and subtler than the familiar label “memory theory.” Memory is the principal psychological means by which present consciousness extends to the past, but Locke repeatedly says that sameness of consciousness—not the faculty or occurrence of memory as such—constitutes personal identity (Thiel, 2011; Strawson, 2011; Yaffe, 2011). The prince-and-cobbler case makes the point: were the prince’s consciousness, including awareness of his past life, transferred to the cobbler’s body, the resulting person would be the prince though the man would be the cobbler. Neither bodily continuity nor sameness of immaterial soul is sufficient without consciousness.

“Person” is also a probative term. Consciousness joins actions to the self that is concerned for its own future happiness and misery, thereby grounding accountability, reward, punishment, repentance, and anticipation. This “concernment” is not an external legal convention but an affective structure of consciousness: pleasure and pain matter because they are experienced as mine. Locke’s theory thus integrates phenomenal awareness, diachronic selfhood, practical concern, and moral agency within one architecture.

Metaphysical Agnosticism About the Conscious Subject

As a paragon of rigorous, tough-minded thinking, Locke refuses to identify consciousness with an independently known mental substance. Our ideas of both material and spiritual substance are obscure suppositions of an unknown support for observable powers. Accordingly, we cannot determine by examining our ideas whether God has joined an immaterial thinking substance to an organized body or has given suitably organized matter itself the power to perceive and think (Locke, 1689/1975). Locke regarded an immaterial soul as more probable, but his theory of consciousness and personal identity does not depend upon it.

This agnosticism is philosophically decisive. A single person might, in principle, persist through changes of underlying substance if the same consciousness continued; conversely, the same soul without continuity of consciousness would not preserve the same person. Consciousness is therefore individuated functionally and first-personally before its metaphysical bearer is settled. Locke neither reduces experience to matter nor makes immaterial substance explanatory; he relocates the central question from “What substance thinks?” to “What constitutes a conscious self?”

Importance, Tensions, and Legacy

Locke’s achievement is to make consciousness do several foundational jobs at once: distinguish genuine thinking from unconscious nonoccurrence, disclose the subject’s existence with maximal certainty, organize phenomenal contents as experiences for a subject, constitute the self at a time, and extend that self into a morally accountable person. His vocabulary and arguments helped transform consciousness from the older domain of conscience and moral knowledge into a general philosophical concept of subjective mental awareness.

The theory also faces enduring difficulties. Empirical evidence for unconscious perception, cognition, and motivation undermines Locke’s apparent equation of thinking with consciousness. Butler’s charge of circularity and Reid’s “brave officer” objection challenge whether remembered consciousness can constitute identity without presupposing it and whether identity remains transitive across memory gaps (Butler, 1736; Reid, 1785). More fundamentally, Locke does not explain the unity of simultaneous experience, the causal production of qualitative character, or the ontological status of a consciousness capable of persisting independently of any specified substance. Even so, his framework remains pivotal and exemplary: modern debates about phenomenal awareness, self-representation, psychological continuity, embodiment, moral responsibility, and the distinction between persons and organisms still operate within conceptual terrain that Locke largely established.

Placement

Placement in Materialism/Philosophical is a lineage claim, not an ontological one. As noted, Locke was officially agnostic about the substrate of thought and considered immateriality the more probable option. Hume's placement in Materialism/Philosophical is defensible on his own non-substantialism; Locke's is defensible only on what his pioneering ways of thinking enabled downstream. Locke was not a proto-materialist. Rather, he introduced the modern concept of consciousness into philosophy—consciousness as the perception of what passes in one's own mind.

References

Butler, J. (1736). The Analogy of Religion, Natural and Revealed, to the Constitution and Course of Nature. London: James, John and Paul Knapton.

Chalmers, D. J. (1995). Facing up to the problem of consciousness. Journal of Consciousness Studies, 2(3), 200–219.

Coventry, A. M., and Kriegel, U. (2008). Locke on consciousness. History of Philosophy Quarterly, 25(3), 221–242.

Locke, J. (1689/1975). An Essay Concerning Human Understanding (P. H. Nidditch, Ed.). Oxford: Clarendon Press. [Book II, Chapter xxvii added in the second edition, 1694.]

Reid, T. (1785). Essays on the Intellectual Powers of Man. Edinburgh: John Bell.

Strawson, G. (2011). Locke on Personal Identity: Consciousness and Concernment. Princeton, NJ: Princeton University Press.

Thiel, U. (2011). The Early Modern Subject: Self-Consciousness and Personal Identity from Descartes to Hume. Oxford: Oxford University Press.

Weinberg, S. (2016). Consciousness in Locke. Oxford: Oxford University Press.

Yaffe, G. (2011). Locke on consciousness, personal identity and the idea of duration. Noûs, 45(3), 387–408.