Descartes on Selfhood, Conscientia, the First Person and Beyond

Abstract: I discuss Descartes’ metaphysics of selfhood, and relevant parts of contemporary philosophy regarding the first person. My two main concerns are the controversy that surrounds Descartes’ conception of conscientia, mistranslated as “consciousness,” and his conception of selfhood and its essential connection to conscientia. “I”-thoughts give rise to the most challenging philosophical questions. An answer to the questions concerning the peculiarities of the first person, self-identification and self-ascription, is to be found in Descartes’ notion of conscientia. His conception of selfhood insightfully informs his conception of personhood. I offer a unified account of selfhood, conscientia, the first person, and personhood anchored in the self’s authority of reason and autonomy of freedom.

Keywords: René Descartes, conscientia, first person, selfhood, personhood, freedom.

let the mind know itself not as if it were seeking an absent self, but let it set the attention of its will, by which it was wandering among other things, upon itself and let it think itself.

Concern with the metaphysics of selfhood is concern with the metaphysics of conscientia and the relation between two distinct but non-independent elements of first-person thoughts: self-identification and self-ascription. First-person thoughts, or “I”-thoughts, “give rise to the most challenging philosophical questions, which have exercised the most considerable philosophers” (Evans 1981, 300) through the centuries. Here, I examine Descartes’ conception of selfhood and its essential connection to conscientia, and some parts of contemporary philosophy on the first person.

I argue that an important part of an answer to the question concerning the peculiarities of the first person—self-identification and self-ascription—is to be found in the notion of conscientia, as used by Descartes, which presupposes and forces into the centre of our thought and enquiries the notion of the self.

A striking aspect of Descartes’ lasting legacy is his celebrated first and most indubitable truth, Ego sum, ego existo, “I am, I exist” (Second Meditation, AT 7, 25; CSM 2, 17), which still prompts us to reflect deeply on a number of issues regarding the self, conscientia, and the first person. The metaphysical status of and the relations between all three remain a serious challenge of our times: the cogito is ahistorical. Descartes writes: “I devoted as much effort [to the Second Meditation] as to anything I have ever written” (Second Set of Replies, AT 7, 137; CSM 2, 98). This is unsurprising, since it grapples with one of the most recalcitrant philosophical problems—that of the self—which involves “some of the profoundest philosophy” (Evans 1981, 300).

The I of the Meditations is not a mere logical/formal self; logical/formal selves cannot think, act, judge, or synthesise. The logical self is implied by the real self, a subject of thought and activity, or “whatever it is about which a thinker thinks when he thinks about himself” (Evans 1982, 259, n. 2). The self is neither an appendage to personhood—added or subtracted according to our theories—nor supernatural. The self, a natural real and true entity, is the metaphysical and explanatory ground, a source of a unified notion of personhood. Drawing on Descartes’ statement: “my whole self […] can be affected by various […] bodies that surround it” (AT 7, 81; CSM 2, 56), I demonstrate that the “whole self” is the embodied self: a person. I am “a single person with both body and thought [mind]” (letter to Elisabeth of Bohemia, 18 June 1643, AT 3, 694; CSMK, 228).1

It is Descartes’ conception of selfhood that informs his conception of personhood. Once our understanding is freed from intellectual habits that persist in current debates concerning Descartes’ metaphysics (see par. 4 below), his views offer an opportunity to draw important insights.

Examining Descartes’ metaphysics of conscientia, the aim is not to give a general account of the notion, given its long history, but to offer an elucidation in two inextricably related parts. The first, in par. 5, elucidates conscientia as self-knowledge in a dual sense—not in our modern sense of self-knowledge of immediate access to one’s mental states, “given free by introspection”; conscientia is a hard-won achievement, as we shall see. The second part, in par. 6, elucidates conscientia as self-consciousness, since only a self-conscious being is capable of embarking on self-knowledge and self-scrutiny.

Drawing on this, in par. 7, I examine the relation between cogitatio and conscientia and consider the view that Descartes defines cogitatio in terms of conscientia, or treats them as equivalent, labelled “Descartes’ definition of thought” (henceforth, the controversy).

In par. 8 I demonstrate Descartes’ significant turn in the metaphysics of mind, and in par. 9 I argue that Descartes anticipates Frege’s subjective/objective distinction. Finally, in par. 10 I turn to the two elements—self-identification and self-ascription—leading from selfhood to personhood.

Ultimately, the aim is to develop a basis for a unified account of selfhood, conscientia, the first person, and personhood anchored in the idea of the self’s authority of reason and autonomy of freedom exemplified in Descartes’ works. Such an account, if successful, would resolve the controversy and be philosophically the closest to Descartes’ metaphysics.

But first, in par. 3 I offer a preliminary elucidation of Descartes’ conception and use of conscientia. This enables me, in par. 4, to begin clearing the ground of some misconceptions of and misattributions to Descartes’ philosophical commitments. This task is necessary if I am to proceed in an orderly way and demonstrate conscientia’s centrality to his metaphysics.

Conscientia is a complex term with a long history, in classical and mediaeval Latin, and originally meant shared knowledge (with other subjects), and which in “the course of history […] became associated with one’s own knowledge about one’s own wrongdoings” (Hennig 2007, 474). Given its long history, a general account of conscientia requires another paper.2 Here, in light of the complexity of conscientia and the lack of a “single modern expression of the term” (Hennig 2007, 459 and 456), I shall attempt to elucidate, not analyse, reduce, or define it.

Drawing on Descartes’ affinity with the classical Greek philosophers,3 I trace the notion of conscientia back to the Delphic injunction γνῶθι σεαυτόν (know thyself, nosce teipsum),4 through Plato’s preoccupation with it,5 to the way conscientia and conscius are used by Descartes in directing his metaphysical enquiry. This is not arbitrary, but based on good reasons, drawing on what Descartes writes: “there is no more fruitful exercise than attempting to know ourselves” (Description of the Human Body, AT 11, 223–24; CSM 1, 314). And again: those endowed with the use of reason “have an obligation to employ it principally in the endeavour to know [God] and to know themselves” (letter to Mersenne 15 April 1630, AT 1, 144; CSMK, 22) In this sense, I understand conscientia as self-knowledge in a substantive sense, with metaphysical, epistemic, and moral significance. Conscientia as self-knowledge entails conscientia as self-consciousness, as I shall argue later.

What can be pointed out right away is that the English editions somewhat misleadingly translate conscientia as “consciousness,” giving the impression that it is used in the modern sense traceable to the late-seventeenth and early-eighteenth centuries. This is then carried over into the numerous commentaries on Descartes.6 Translating conscientia as “self-consciousness” would have been preferable, because at least it relates to one’s being conscius of oneself as oneself.7 However, both self-knowledge and self-consciousness are necessary, neither on its own is sufficient for Descartes’ metaphysics of selfhood and thereby personhood. Conscientia always has an object: “what is the object of conscientia?” (par. 5 passim).

Descartes uses the French term conscience in the Passions of the Soul, meaning conscience in a moral sense, but also in some letters implying epistemic virtue. The Latin word conscientia does not appear in his masterpiece, the Meditations, only conscius, and that only occasionally. From this it does not follow that conscientia was not central to Descartes’ metaphysical enquiry. In fact the Meditations contains the most rigorous and radical two-fold conception of the concept: with its invitation to the reader to adopt the persona of the meditator, the work effected a self-transformation, and an ontological shift and a metaphysical turn that changed the philosophical world, and that enabled the emerging new sciences to progress.

Descartes uses conscientia in his Replies to Objections, in Principles of Philosophy, in The Search for Truth, and in some letters. What is crucial for now is Descartes’ declaration in the Regulae:

I wish to point out here that I am paying no attention to the way these terms have lately been used in the Schools. For it would be very difficult for me to employ the same terminology, when my own views are profoundly different. […] I shall use what seem the most suitable words, adapting them to my own meanings (Rule Four, AT 10, 369; CSM 1, 14; italics added).

For Descartes the notions of conscientia and conscius are not simply conative but cognitive. Conscius is a cognate of scire, to know, to be cognitively, not simply conatively aware. I consider this in par. 6; for now, the distinction can be seen in his reply to Gassendi’s objection that the meditator “could have made the same inference from any one of [his] other actions” (Fifth Set of Objections, AT 7, 259; CSM 2, 244). Descartes replies: “I may not, for example, make the inference ‘I am walking, therefore I exist’, except in so far as the awareness of walking is a thought”—that is, in so far as the awareness is cognitive and not simply conative: “The inference is certain only if applied to this awareness and not to the movement of the body” (Fifth Set of Replies, AT 7, 352; CSM 2, 244).8

Descartes didn’t use conscientia to mean consciousness in our modern psychological and nonmoral sense, with all its post-Cartesian baggage, nor did he equate thought with consciousness, or claim that the mark of the mind is consciousness.9

The problem with mistranslating conscientia, in other words, is not simply terminological, but has serious substantial implications regarding misattributions to Descartes’ metaphysical commitments by post-Cartesian writers. Not only does the phenomenological school of thought lump Descartes together with Husserlian “phenomenological reduction,” or “bracketing the self,” but also the analytic school of thought over the last hundred years or so attributes to Descartes the fantasy of isolation, introspection, privacy,10 of confining the self within consciousness, of adverting to the sense-data of logical positivists,11 such that how things seem to a subject is how they are.

Some examples of such misattributions will suffice to demonstrate the seriousness of the problem. Misattributions in various writers’ doctrines are accepted by those who follow, partly because of the power and authority of those who “pass them off as true” (Rule Two, AT 10, 362–63; CSM 1, 11), and partly because, through lack of reflection, any misconceptions in such doctrines become widespread inveterate intellectual habits, “fortifying [oneself] with the authority of others […] since truth by itself is so little esteemed” (letter to Mersenne, 30 September 1640, AT 3, 184; CSMK, 153).

Misconceptions typically present the extent of the meditator’s (supposed) inner space as self-standing or self-contained:

in effect Descartes recognizes how things seem to a subject as a case of how things are […] [and faces] up to losing the external world with the inner for consolation [and retreats to and accepts] the availability of infallible knowledge about the newly recognised inner region of reality (McDowell 1998, 239).12

Simmons claims that “Descartes revolutionized our conception of the mind by identifying consciousness as the mark of the mental.” She goes on to say: “I do not deny the revolutionary story” because

while Descartes was indeed unwavering in his commitment to the conscious mark, he had the resources to distinguish different types and degrees of consciousness that make for a richer cognitive psychology than he is typically credited with (Simmons 2012, 1 and 3).

Thiel states that Descartes, unlike Locke, did not see consciousness as a separate act, though it is not easy to determine whether for Descartes consciousness was first-order or second-order. Thiel attributes to Descartes the second-order view (Thiel 2011, 47–8). Given that Descartes never used the notion of consciousness, nor was it available at the time, he cannot be committed either to the first-order or to the second-order view.

Others, in similar vein, claim that for Descartes “consciousness is the defining characteristic of the mind”; the

incorrigible foundations are discovered only in first person, present tense, psychological statements concerning the individual current contents of the introspective gaze: a gaze focusing on objects as heterogeneous as ‘pains’ and metaphysical ‘thoughts about being’ [‘given free by infallible conscious introspection’]. The mind [and ‘its dramatic separation from anything bodily’] becomes a private inner stage (vide Hume’s analogy which, precisely, compares the mind to an internal theatre) […] in which everything ‘mental’ passes chaotically before an unblinking inner eye (Wilkes 1992, 22–3).

Or, the “Cartesian model of self-knowledge [is] analogous to [sensory] observation” (Rorty 1980, 110).

Descartes in fact argues against all these positions, yet through ill-formed intellectual habits the misattributions persist unabated. First, he rejects both the sense–perception–model of self-knowledge, considered of dubious coherence (Shoemaker 1984, 14–5), and introspection, or “internal senses,” since he considers it as unreliable as the external senses13 (Sixth Meditation, AT 7, 77; CSM 2, 53; Second Meditation, AT 7, 23 and 29), as limited in its reach, and as providing no insight into objective standards.

Descartes’ concern is with reason’s clear and distinct perceptions which correspond, are directly and indubitably responsive, to the nature of what is real and true. The two principles—clarity and distinctness, and correspondence—provide sufficient reason that such perceptions are a direct openness to reality, not a veil that shrouds reality.

Secondly, what is clearly and distinctly understood cannot be doubted. In Principles I:45, Descartes elucidates what is meant by a clear and distinct perception: “I call a perception ‘clear’ when it is present and accessible to the attentive mind” (AT 8-a, 22; CSM 1, 208). What does this mean? Attentively determining that it is clear, not simply thinking that it is clear or just being present to the mind, involves subjecting it to the methodic scrutiny and its withstanding that scrutiny (Fifth Set of Replies, AT 7, 379; CSM 1, 207).14

A perception which can serve as the basis for […] indubitable judgement needs [also to be] distinct. […] I call a perception ‘distinct’ if, as well as being clear, it is so sharply separated from all the other perceptions that it contains within itself only what is clear (Principles I:45, AT 8-a, 22; CSM 1, 208),

A distinct perception or “concept is not any more distinct because we include less in it; its distinctness simply depends on our carefully distinguishing what we do include in it from everything else” (Principles I:63, AT 8-a, 31; CSM 1, 215). A perception “cannot be distinct without being clear” (Principles I:45, AT 8-a, 22; CSM 1, 208). Thus whatever is clearly and distinctly perceived is true; it cannot be doubted, and cannot be contradicted, and while concentrating on it the meditator needs no one to guarantee its truth and indubitability.16

Sense perceptions, including sensations of intense pain, can be clear, but “however clear” (Second Set of Replies, AT 7, 145–46; CSM 2, 104) cannot be distinct because they are confused, i.e., mixed (from confundere, mingled or mixed), the mixing of sense and reason.17

Attention, as in “the attentive mind,” “the attentive enquirer,” or “attentively determining” plays a central role in Descartes’ method as set out in the Discourse, in the method of scrutiny, in the order of reasoning that he follows and considers to be “the right way […] to find and explain the truth” (letter to Mersenne, 24 December 1640, AT 3, 266; CSMK, 163; Rule Four, AT 10, 378–79).18 Order in terms of prior/posterior. It proceeds by “analysis [which] shows the true way by means of which the thing in question was discovered methodically tanquam a priori [i.e., prior in the order of discovery]” (Second Set of Replies, AT 7, 155; CSM 2, 110).19 Attention involves a resolute focusing of one’s mind on what is under consideration, or on the way “the thing in question was discovered,” without shifting one’s focus (Christofidou 2013, chapter 7). Descartes’ requirement of an unprejudiced, attentive enquirer marks out attention as a distinctive capacity; inattention can lead to erroneous judgements and irresponsibility (Fourth Meditation).

Thirdly, Descartes does not confine the self within consciousness because, not only he never used “consciousness,” but equally importantly, even in the Second Meditation where his commitments are epistemic not metaphysical, Descartes’ conception of the self conforms perfectly to Evans’s requirement:

just as our thoughts about ourselves [our ‘I’-thoughts] require the intelligibility of [the] link with the world thought of ‘objectively’, so our ‘objective’ thought about the world also requires the intelligibility of [that] link (Evans 1982, 212 and 259).

Nothing in the self’s conception fails to conform to Evans’s requirement, since the intelligibility of such links is part of the self’s clear conception; nor does it prevent the self’s conception of the world as an objective world (Christofidou 2022). The cogito, I shall demonstrate later, has objective universality: “reason is a universal instrument” (Discourse, AT 6, 57; CSM 1, 140).

Fourthly, Descartes is not concerned with infallibility—he finds its strength uncomfortable (Discourse, AT 6, 40).20 Indeed, he writes to Elisabeth of Bohemia: it is

not necessary that our reason should be free from error; it is sufficient if our conscience testifies that we have never lacked resolution and virtue to carry out whatever we have judged the best course” (letter to Elisabeth, 4 August 1641, AT 4, 266–67; CSMK, 258).

Nor is he concerned with self-intimation, incorrigibility, or irresistibility. His concern is with indubitability: with what cannot be doubted (attentively adducing reasons that can withstand the methodic scrutiny), and not with whether he or anyone else, psychologically or epistemically, can or cannot doubt it.

Fifthly, the distinction between appearance and reality, seeming and being, was addressed as early as in the closing passage of the First Meditation, where the meditator asserts his autonomy of freedom in defiance of the demon: however powerful the demon is, “I shall […] do what is in my power [‘to suspend my judgement’ and] resolutely guard against assenting to any falsehoods” (AT 7, 23; CSM 2, 15; italics added).

Descartes does not conflate seeming and being; he explicitly states: “There is nothing at all that I asserted ‘with confidence’ in the First Meditation: it is full of doubt throughout” (Seventh Set of Objections with Replies, AT 7, 474; CSM 2, 319)—clearly missed by inattentive critics. He suspends judgement, and neither accepts nor finds consolation in how things seem; nor does he affirm “the opposite of what is doubtful” (AT 7, 465; CSM 2, 356). On the contrary, the resulting instability in the edifice of opinions provides a ground for rational discomfort, aporia (in Socrates’ and Aristotle’s sense). A little reflection shows that doubting involves no affirmation or denial.

Furthermore, his experiences cannot be private, since self-critical reflection and the capacity to suspend one’s dubitable beliefs require adopting reason’s objective standpoint, “rightly conducting one’s reason and seeking the truth” (Discourse, AT 6, 1; CSM 1, 111). There is no picture of the so-called inner space in which what I seem to see or hear is accepted as how things are, or considered as infallible or, absurdly, as knowledge. Attributions of such views to Descartes are distortions through the post-Cartesian lenses of modern theories and persistent intellectual habits.

Sixthly, and following from the previous point, for Descartes knowledge—scientia—is metaphysically basic, not subject to the reduction or analysis that preoccupies much contemporary epistemology. The foundations of scientia must be objective, not time-bound and not, absurdly, the contents of one’s psychological states of consciousness. Scientia requires stability and lastingness—as Descartes makes clear in the opening paragraph of the First Meditation (AT 7, 17; also The Search for Truth, AT 10, 513)—indubitability because of its inseparability from truth, clarity and distinctness, and reason’s authority and its internal relation to the autonomy of freedom (Christofidou 2009b; Christofidou 2013). No cognitio “that can be rendered doubtful seems fit to be called scientia” (Second Set of Replies, AT 7, 141; CSM 2, 101).

In Descartes’ distinctive conception of freedom, there is no primacy either of practical or of theoretical reasoning. Freedom in its internal relation to reason, the highest grade of freedom, is necessary not only for practical reasoning, but equally for theoretical reasoning21—the unity of the self is not severed in Descartes’ conception. What can be clearly and distinctly understood is true and real; it cannot be doubted and cannot be contradicted.

Descartes is not, however, in the grip of a fantasy that reason unaided “by imagination, sense-perception and memory” can give us understanding of a world of corporeal objects.22 He considers observation, pictorial illustrations, experimentation, testing, and correction to be necessary to the spirit of scientific enquiry (Rule Twelve AT 10, 411 passim; also letter to Plempius for Fromondus, 3 October 1637, AT 1, 421).

Seventhly, for Descartes, mind and body are really distinct in their essence and can exist separately, as the conclusion of the real distinction argument states clearly (Sixth Meditation, AT 7, 78). Real distinction implies separability, not actual separation—a mere logical possibility that many commentators and critics through the centuries to the present day have not grasped—a failure resulting in volumes of unfounded criticisms.

Addressing the question “what is the object of conscientia?,” I begin by considering the first part of my two-part elucidation of conscientia as self-knowledge in a dual sense:

1. knowledge of oneself in terms of the readiness to scrutinise one’s preconceived opinions and wrongdoings (including moral akrasia); to cross-examine one’s ill-formed intellectual habits or epistemic vices; to purge oneself of all this and acquire the epistemic and moral virtues of open-mindedness and objectivity. Purging oneself of all this is what is meant by “rigorous scrutiny.”

2. knowledge of what the self is, the very entity fundamental to the possibility of any other forms of conscientia—including moral conscience.

Conscientia in the first sense retains the traditional meaning of “shared knowledge,” but now one’s knowledge is shared with one’s intellect23 in subjecting it to rigorous cross-examination (as might be said to occur in Plato’s Timeaus, 90 a–d). It exemplifies the value of self-knowledge for any thinker who engages in self-examination.

The objects of self-knowledge, in this sense, are the self’s commitments. The self is conscius, cognitively aware, that the content of his thoughts, of his opinions, his acceptance of Scholastic principles, can be subject to doubt. To embark on such scrutiny is to be committed to an evaluation by objective standards: truth, reasons that withstand scrutiny, and (anticipating the discovery of the principle of) clarity and distinctness. This is inherent in Descartes’ method of doubt, his intellectual tool, resolutely adopted through perseverance, individual effort, and practice by the searcher for what is true and real; crucially, it requires the joint efforts of reason’s authority and its internal relation to the will’s autonomy of freedom.

Thus the meditator’s primary task is to free reason from the bondage of external authority and preconceived opinions, and to free the will from prejudices and ill-formed habits that enslave it, in order to be at one with reason, not pulling in opposite directions, and to begin operating “within the bounds of truth” (Second Meditation, AT 7, 30; CSM 2, 20). Self-critical examination and the capacity to suspend one’s dubitable opinions presuppose reason’s objective standpoint—a faculty that “must tend towards the truth, at least when we use it correctly” (Second Set of Replies, AT 7, 144; CSM 2, 103). It is, after all, reason rightly conducted (Discourse, AT 6, 1) “which aspires without limit to ever greater and better things” (Third Meditation, AT 7, 51; CSM 2, 35), and “allows us to reach vastly beyond ourselves” (Nagel 1997, 71)—towards truth and objectivity. Reason’s raison d’etre is openness to objectivity and truth, not its own isolation; reason’s openness can be considered a virtue, both epistemic and moral. Searching for truth is a basis of the very idea of objectivity. Descartes “is right even here” (Nagel 1997, 67, n. 11).

In Descartes’ hands the Socratic elenchus is first self-administered,24 but it does not remain merely self-directed, since in self-scrutiny the mind is at the same time world-directed: what ultimately can survive the elenchus is truth.

Conscientia in the second sense also requires Descartes’ special and invaluable methodic scrutiny in order to cross-examine one’s opinions of what the self is. Conscientia is just as much about understanding clearly and distinctly what it is to be a self, as understanding that I am distinct from the objects of which I can have knowledge25—understanding the “fundamental ground of difference” (Evans 1982, 107)—prompting some of the deepest philosophical questions. The object of conscientia, in this sense, is the self itself. It involves reason’s grasping what the self is, grasping its “nature as distinctly as possible” (Second Meditation, AT 7, 28; CSM 2, 19; Descartes’ commitments in this meditation are epistemic not metaphysical: see AT 7, 8)—graspable by anyone who attentively reasons “in an orderly way” (Principles I:7 and 10; AT 8-a, 6–7 and 8; CSM 1, 194).

Only if we conflated intellectual clear and distinct perception with sensory perception would we think that the former is paradoxical or self-defeating because the self eludes its own perception, or that the self is “observationally systematically elusive.”26 As Descartes explains: “the mind must be diverted” from sensory perception—“from this manner of [perceiving] things” (French edition)—and come to “realise that none of the things that the imagination [or the senses] enable me to grasp is at all relevant to this knowledge of myself which I possess” (Second Meditation, AT 7, 28; CSM 2, 19; letter to Mersenne, July 1641, AT 3, 393–94; also par. 8.1 below) Descartes is not rejecting the senses (which would be nonsensical), but is drawing the bounds of sense.27

Conscientia brings home to us the realisation of our finiteness—a realisation that stems, not simply from the mortality of the subject, but from the fact that we are doubting, self-scrutinising, searching for truth—and stresses that reality is potentially greater than we can grasp, that we cannot achieve the totality of truths, or “the absolute conception of reality” (Williams 1978, 65; also Christofidou 2013 passim). We cannot overestimate the vastness of the universe (Principles III:1). But that should not frustrate our enquiries into what is real and true. On the contrary, the recognition of the vastness of the universe is uplifting, liberating our reflections from the threat of subjectivism, the fall into relativism, parochialism, or scepticism regarding reason’s ability to understand the nature of reality—and there is a world of difference between a conception that strives for the possibility of truth and objectivity, and one that attempts to rule it out. Nor does it force upon us utter noumenal ignorance of the nature of the self.

Clear and distinct ideas are sufficient for the attainability of any determinate facts, since with “the right use of reason” and following “the advice of our reason we have left undone nothing that was in our power” (letter to Elisabeth, 4 August 1645, AT 4, 266–67; CSMK, 258). Thus, although we do not have complete knowledge of anything, we can have knowledge that something is complete, or that it is a true and real entity. Any properties of which we are unaware, or which we might conceive as belonging to it, however, must be consistent with its principal attribute, which constitutes “its essence and to which all its other properties are referred” (Principles I:53, AT 8-a, 23; CSM 1, 210; also AT 7, 220–23; letter to Gibieuf, 19 January 1642, AT 3, 477–78).

Conscientia in its dual sense and the principle of clarity and distinctness are necessary to Descartes’ groundbreaking undertaking, since the search for and attainability of a new metaphysics is not independent of, but requires the attainability of freedom and its internal relation to reason, restoring the self as locus of authority and autonomy, as against the authority of theology.

Conscientia in its dual sense is a hard-won achievement. Descartes’ notion is substantially different in nature and purpose from the modern notion of self-knowledge. This hard-won achievement stems from our nature as thinking, acting, free subjects and agents. Self-knowledge is key to the attainability of virtue, moral and epistemic, and of self-mastery—hence my tracing conscientia to the Delphic injunction (as explained above). It can be taken to constitute the beginning of the human search for wisdom (Principles I:12 and 41, AT 8-a, 9 and 20), and for Descartes and the great philosophers of the past it is considered to be bound up with the very idea of philosophy. The two senses of conscientia are not separate, even if for explanatory purposes we can distinguish between them.

The second part of my discussion of Descartes’ use of conscientia elucidates it as self-consciousness. Self-consciousness is not identical with reflection; our acts, perceptions, knowledge are not accompanied by a further act of reflection (even if a self-conscious being is able to reflect on itself, on its acts, knowledge, etc.).28 Knowledge does not “require reflective knowledge, i.e., knowing that we know, and knowing that we know that we know, and so ad infinitum. This kind of knowledge cannot possibly be obtained about anything” (Sixth Set of Replies, AT 7, 422; CSM 2, 285).29 I begin my elucidation with a passage central to the controversy.

In his reply to Hobbes, Descartes explains that the intellectual and sensory acts of the mind,

which we call ‘acts of thought’, such as understanding, willing, imagining, having sensory perceptions, and so on […] all fall under the common concept of thought [cogitatio], or perception [perceptio], or conscientia, and we call the substance in which they inhere a thinking thing or a mind […]. [The] acts of thought have nothing in common with corporeal acts, and thought, which is the common concept under which they fall, is different in kind from extension, which is the common concept of corporeal acts (Third Set of Objections with Replies, AT 7, 176; CSM 2, 124; italics added; letter to Mersenne, May 1637, AT 1, 366).

Furthermore, a clear and distinct understanding reveals that “there is an intellectual act included in their essential definition”—in what they are (Sixth Meditation, AT 7, 78; CSM 2, 54). What this entails is that for Descartes the content of both intellectual and sensory acts of mind is conceptual, and has significant implications in the metaphysics of mind (par. 8), given Descartes’ distinction between the acts of thinking, sensing, etc., and what the acts are about—the world-directedness of the mind (par. 9).

This is not a mere speculative thought, but a metaphysical precondition for what it is to be a thinking, acting, imagining, sensing being who can not only think of itself, but think of itself as itself (as I shall demonstrate in what follows).

A note of clarification. For Descartes, “within us,” “inhere in,” “contained in” denote ontological and explanatory dependence, not a container or a causal relation—the mind is not an amphora. “Contained in” can also mean “true of a thing in terms of its nature”: “When we say that something is contained in the nature or concept of a thing, this is the same as saying that it is true of that thing, or that it can be asserted of that thing” (definition 9, AT 7, 162; CSM 2, 114).

In par. 3, I explained conscius as meaning cognitively, not merely conatively or sensorily, aware; my explanation is now vindicated, since both our cognitive and sensory acts include in their essential definition an intellectual act. We can thus distinguish two kinds of cognition in Descartes’ conception: a cognition of reason, and a cognition of reason mixed with the senses. What this means is that, though our a priori thoughts may require no other faculty except the faculty of reason, our a posteriori thoughts, sensations, emotions, sense perceptions, etc., fall also under the faculty of sensory awareness—the mixing of reason and the senses.

For Descartes, being sensorily aware cannot be conflated with post-Cartesian views of “the myth of the given,”30 or of merely sensory or non-conceptual. Furthermore, the mixing of reason and sense ensures the active character of perception, and gives weight to the idea that understanding an object (however minimally) requires directing our attention to it. This can also help us get as clear as possible about the source of our concepts: the a priori concepts of reason, which nevertheless can figure in our experience, and those concepts which can be acquired only from experience, requiring the mixing of reason and the senses. In this way we can begin to determine their use and applicability safely and invaluably.

Descartes’ reply to Hobbes, cited above, is one of the passages that a number of scholars use to argue that he treats conscientia and cogitatio as equivalent.31 This raises the question: “what does Descartes understand by cogitatio?”

In clarifying cogitatio, there is a distinction between cogitatio or cogitationes, “taken as modes […] of the mind […] as many different thoughts [i.e., acts]” (Principles I:64, AT 8-a, 31; CSM 1, 215) on the one hand, and the common concept of thought, on the other. Neither the modes of thought nor the acts of thought can be equivalent to the common concept of thought; rather, they fall under it—they presuppose it. Descartes explains to Hobbes: “‘thought’ is sometimes taken to refer to the act, sometimes to the faculty” (AT VII, 174; CSM 2, 123), but both the acts and the faculties fall under the common concept of thought.

Thought, under which the acts of thought fall, is a simple notion or nature—it is unanalysable, not made up of parts (Rule Twelve, AT 10, 419)—and it is common because it relates to all acts of thought. Thought, cogitatio, in this sense, is the principal attribute of the mind: our intellectual and sensory acts, faculties, capacities presuppose, fall under, the principal attribute of thought, which constitutes and expresses (makes known, manifests) the essence of mental substance; the attribute of thought is the mark of the mind.

Attribute is no ordinary property, or an aspect, but a simple common notion, along with substance and essence, ascribed indifferently to corporeal and mental entities.32 Unlike attribute, substance, and essence, simple common notions such as existence, duration, etc. (Rule Twelve, AT 10, 419), are modes “under which we conceive a thing in so far as it continues to exist” (Principles I:55 and 57, AT 8-a, 26 and 27; CSM 1, 211); they too are ascribed indifferently to all classes of finite existing things.33 The attribute of thought is a simple common notion, since it relates to all acts of thought but to no other class of things.

As we have seen, clear and distinct understanding of these acts reveals that an intellectual act is included in what they are, and without which they wouldn’t be acts of a thinking, acting, sensing being. They all “contain some reference to [the attribute of] thought,” and the distinction between them and the mind is modal (Sixth Meditation, AT 7, 78; CSM 2, 54). That is, they can neither be nor be understood “without an intellectual substance to inhere in”34—presupposing its true unity (Second Meditation, AT 7, 28; CSM 2, 54; Third Meditation, AT 7, 34; Fourth Meditation, AT 7, 56–7; Sixth Meditation, AT 7, 78–9; also par. 7.2 below.) None of them can be ontologically, metaphysically, and explanatorily independent of the attribute of thought, which in turn is inseparable from the mind.

Conscientia is also a simple common notion, and presupposes the principal attribute of thought: that is, being a self-conscious subject entails being a thinking subject. If there is conscientia, there must be a thinking subject. The key point is that a self-conscious subject, by the very fact that it is a thinking subject, is capable of reflecting upon itself and upon the world, capable of self-knowledge in its dual sense.

Thus conscientia, both as self-consciousness and as self-knowledge, cannot be equivalent to cogitatio the principal attribute, nor can it be equivalent to the many different modes of thought, or the many different acts of thought. Consequently, there is no ambiguity in Descartes’ reply to Hobbes that acts of thought “all fall under the common concept of cogitatio, or conscientia,” nor does he treat them as equivalent, since the latter presupposes the former, and “we call the substance in which [the acts] inhere a thinking thing or a mind” (AT 7, 176; CSM 2, 124). Put differently, “falling under” the common concept of conscientia presupposes the common concept of cogitatio, the attribute of thought.

For Descartes the mark of the mind is the attribute of thought, contrary to Kenny’s claim that for Descartes “consciousness is the defining feature of the mind an especially hidden and private realm,” not “rationality [as it was ‘for his predecessors’ which], is not […] private.” Ignoring the attribute of thought—the true mark of the mind—is important to Kenny’s polemic against Descartes, which has become an inveterate intellectual habit. Kenny openly states that he follows “the polemic of Ryle” (Kenny 1989, vii and 9; regarding Ryle’s polemic, see Christofidou 2018).

My elucidation is also consistent with Descartes’ explanation in his letter for [Arnauld], that in Principles I:63 and 64, he

tried to remove the ambiguity of the word ‘thought’ […] [stating that] thought, or a thinking nature, which I think constitutes the essence of the human mind, is very different from any particular act of thinking. It depends on the mind itself whether it produces this or that particular act of thinking, but not that it is a thinking thing. […] So by ‘thought’ I do not mean some universal which includes all modes of thinking, but a particular nature, which takes on those modes, just as extension is a nature which takes on all shapes (letter [for] Arnauld, 29 July 1648, AT 5, 221; CSMK, 357; italics added).

Descartes abandoned “the universals of the dialecticians” (Fifth Set of Replies AT 7, 380; CSM 2, 261; Principles I:59, AT 8-a, 27–8), which are derived through the senses by a process of abstraction of common features of sensory objects of the same kind, omitting what is peculiar to each. They are not distinct; they have no true unity, only a form of aggregation imposed by us. They are constructs of the mind as it struggles to make sense of its sensory experience, and even if useful for such heuristic purposes, they are inadequate for Descartes’ new metaphysics and a new science of mathematical physics.

He introduced simple notions which relate “to many things an idea which is in itself singular,” that is, whose referent is a singular true nature (letter to Regius, 24 May 1640, AT 3, 66; CSMK, 148). On Descartes’ reversal of the order of reasoning and his abandoning of Scholastic universals and abstractions, we understand the general in the singular true nature graspable by reason. The simple notions and simple common notions are true, and prior in the order of reasoning. In order to know what are the simple intellectual notions, such as thinking, willing, and doubting, the simple purely material notions, such as extension, and the simple common notions such as existence, unity, and duration, “all we need is some degree of rationality” (Rule Twelve, AT 10, 419; CSM 2, 45). They are grasped by the intellect guided by the natural light of reason (which is not arbitrary but a precondition of conscientia).35 We do not

have to rack our brains trying to find the “proximate genus” and the “essential differentia” which go to make up their true definition. We can leave that to someone who wants to be a professor or to debate in the Schools (The Search for Truth, AT 10, 523; CSM 2, 417).

It might be argued against my discussion that, apart from his reply to Hobbes, there are other passages adduced by commentators when stating that Descartes defines cogitatio in terms of conscientia.

In light of the seriousness of the controversy, what needs to be addressed first is: “what does Descartes mean by ‘definition’?” It is clear from the above quotation that Descartes does not mean Scholastic definition, linguistic, conventional, or logical definition: “our attempts to define [simple notions would make them] more obscure” (AT 10, 523; CSM 2, 417); “Matters which are very simple and self-evident are only rendered more obscure by logical definitions, and should not be counted as items of knowledge which it takes effort to acquire” (Principles I:10, AT 8-a, 8; CSM 1, 195).

By “definition,” Descartes means a true or real definition, founded in reality, in what the simple notions are, in their essential nature; hence, “an intellectual act [is] included in their essential definition.” As Spinoza, following Descartes, states: “the true definition of each thing neither involves nor expresses anything except the nature of the thing defined” (Ethics I, proposition 8, scholium 2, Spinoza 1996, 5). Thus there is no room for stipulation because the simple notions “already have a sense” (Frege 1979, 210). For Descartes, followed by Spinoza, what is real is true, and what is true is real. Real or true definitions make known the essence of entities or simple notions, in contrast to linguistic, logical, or nominalistic definitions, which are purely terminological. True notions are graspable by reason; it is not up to us to make them so: “our mind is not the measure of reality or of truth; but certainly it should be the measure of what we assert or deny” (letter to More, 5 February 1649, AT 5, 274; CSMK, 364), implying epistemic and moral responsibility.

As Descartes explains, “we cannot have any thought without a foundation [in reality]” (letter to ***, 1645/1646, AT 4, 348–50; CSMK, 279–80). Any true thought we can have must be founded in something real: “whatever is true is something” (Fifth Meditation, AT 7, 65; CSM 2, 45), not simply true of something; “truth is essentially indivisible” (Seventh Set of Objections with Replies, AT 7, 548; CSM 2, 374). It is metaphysically basic “however epistemological we may allow our formulation to be of its marks” (Wiggins 1996, 274) indefinable, irreducible, indivisible; “truth consists in being,” in what is real—the intrinsic denomination of truth (letter to Mersenne, 16 October 1639, AT 1, 597–98; CSMK, 139). He writes: “I have no criterion [of truth] except the natural light [of reason]” (AT 1, 596; CSMK, 139). Similarly, Spinoza states: “truth is its own standard” (Ethics II, proposition 43, scholium, Spinoza 1996, 59).

Simple notions are the simplest constituents of knowledge, and are known through themselves (Principles I:10). Their self-evidence “is the basis for all the rational inferences we make” (Rule Twelve, AT 10, 419; CSM 1, 45). They are such that they focus the attentive thinker’s direct apprehension, or singular thought, on that notion as a notion in and of itself.

Let’s now consider two passages central to the controversy. In the Arguments appended to the Second Set of Replies, in definition 1 Descartes states:

Thought. I use this term to include everything that is within us in such a way that we are immediately conscious of it [ut eius immediate conscii simus]. Thus all the operations [acts] of the will, the intellect, the imagination and the senses are thoughts. I say ‘immediate’ so as to exclude the consequences of thoughts; a voluntary movement, for example, originates in a thought but is not itself a thought (AT 7, 160; CSM 2, 113).

By the term ‘thought’, I understand everything which we are aware of [nobis consciis] happening within us, in so far as we have awareness of it [conscientia est]. Hence, thinking is to be identified here not merely with understanding, willing and imagining, but also with sensory awareness […] since they relate to the mind, which alone has [for example] the sensation or thought that it is seeing or walking (AT 8-a, 8; CSM 1, 195).

Both in definition 1, and in Principles I:9 Descartes consistently holds that “thought” in this context, refers to the various acts of the mind. This is perfectly consistent with Principles I:63 and I:64 (see par. 6.2 above), in which he refers to “thought” as the principal attribute of the mind: acts of thought fall under the true and real principal attribute of thought constituting the essence of mind.

we are not always aware of the mind’s faculties or powers, except potentially. By this I mean that when we concentrate on employing one of our faculties, then immediately […] we become actually aware of it (Fourth Set of Replies, AT 7, 247; CSM 2, 172).

“We cannot have any thought [any act of thought] of which we are not aware [conscii] at the very moment when it is in us […] [we] are always actually aware of the acts or operations of our minds” (AT VII, 246; CSM 2, 177; italics added; First Set of Replies, AT 7, 107; Third Meditation, AT 7, 49; Passions I:19, AT 11, 343).

It is “the operations [acts] of the mind,” when the mind enacts them, of which we are immediately conscii (AT 7, 232 and 247; CSM 2, 113), and of which Descartes says in his reply to Caterus: “there can be nothing within me of which I am not in some way conscius” (First Set of Replies, AT 7, 107; CSM 2, 77).36

There is no suggestion, implicit or explicit, that he defines cogitatio in terms of conscientia. To help settle this long running debate, pulling my discussion in par. 6 and par. 7 together, the difference between cogitatio and conscientia can be summarised thus:

First, cogitatio can be taken to refer to many different thoughts, or to many different acts of thought; cogitatio is also taken to refer to the principal attribute of thought. But conscientia cannot be taken to refer either to different thoughts, or to acts of thought, or to the attribute of thought which is presupposed by conscientia. Secondly, and equally importantly, the objects of conscientia, apart from the self, are the acts of thought and what they are about: their world-directedness. But the objects of the acts of thought cannot be the acts of thought, on pain of absurdity. For example, the object of an act of sense perception, or what the act is about, its content, is, say, the sun itself (Third Meditation, AT 7, 39). But the act is not part of the content (see par. 9 below).

Therefore, any arguments that Descartes treats cogitatio and conscientia as equivalent or synonymous, or that he defines one in terms of the other, cannot be sustained.

The significance of all this cannot be overestimated and has its basis in the Meditations. Referring to his reply to Caterus (AT 7, 107), Descartes writes to Mersenne: “What I say later, ‘nothing can be in me, that is to say, in my mind, of which I am not aware’ [conscius], is something which I proved in my Meditations” (letter to Mersenne, 31 December 1640, AT 3, 273; CSMK, 165–66).

In the Second Meditation, the meditator raises the question “What then am I?,” and after an unrelenting cross-examination, he replies: “A thing that doubts, understands, affirms, denies, is willing, is unwilling, and also imagines and has sensory perceptions” (AT 7, 28; CSM 2, 19). The last two conjuncts are not mere afterthoughts—nothing is an afterthought in the Meditations—but are of groundbreaking significance in the metaphysics of mind (Christofidou 2021; Christofidou 2022). They challenge the prevailing Aristotelian doctrine of a sharp division between the sensory soul (psyche, anima) and the intellectual mind (nous; Christofidou 2009a), which had dominated the philosophical world for centuries, and move towards Descartes’ conception that both intellectual and sensory acts are dependent on, are inseparable from, the single mind (mens) (AT 7, 28–9), which presupposes the unity and irreducibility of “the same I”: “Ego sum res cogitans […] & sentiens” (AT 7, 28; CSM 2, 19); “I consider the mind not as a part of the soul [anima] but as a thinking soul [mens] in its entirety” (Fifth Set of Replies, AT 7, 356; CSM 2, 246).

The two conjuncts demonstrate Descartes’ new beginning: a significant turn in the metaphysical of mind. They highlight his insightful conception and defence of the true unity of mind, the unity of conscientia (as self-consciousness and as self-knowledge), a conception that has far-reaching consequences for our concerns, since it is not only rational acts but also sensory acts which include in their essential definitions an intellectual act. The nature, irreducibility, indivisibility sive unity of the mind is not constructed by us, but founded in reality—and reality is more than physical reality:37 the mind forecloses any attempts to analyse it in terms of “things to which it [doesn’t] pertain.” Otherwise, “we cannot help going wrong” (letter to Elisabeth, 21 May 1643, AT 3, 666; CSMK, 218).

The mind, for Descartes, is neither disembodied nor supernatural; it is a real and natural entity.38 It may be true that what is physical is natural, but it’s fallacious to infer that what is natural is physical, or reducible to, or grounded in the physical. For Descartes: “the word ‘mind’ is taken in the ordinary sense,” a “thinking thing which in common usage is termed a ‘mind’” (Seventh Set of Objections with Replies AT 7, 558 and 525; CSM 2, 558 and 357). A common usage cannot be dubbed supernatural or metaphysically extravagant.

Yet, all this seems to have gone largely unnoticed in the vast literature on Descartes, in the vaster literature on phenomenology and intentionality, and in the current controversy between those who argue that our rational capacities are independent of and additional to our sensory capacities, and those who argue that our rational capacities transform our sensory capacities—dubbed the “additive” and “transformative” approaches, respectively.39 Descartes’ argument that “an intellectual act is included in the definition” of all acts of the mind, cuts across the current controversy which gives priority to the rational over the sensory either by being added to, or by transforming the sensory, and the controversy regarding the conceptual/non-conceptual content. Descartes’ conception provides a clear path over these seemingly unbridgeable chasms in contemporary debates.

The self has the capacity for self-ascription and self-identification; for self-reflection, self-scrutiny, self-determination, and self-mastery. Such a capacity manifests the power of “a thinking thing or a mind,” capable of acting on itself. As Arnauld acknowledges: “the mind meditates attentively and keeps its gaze fixed upon itself” (Fourth Set of Objections, AT 7, 197; CSM 2, 138).

The self’s mind and its power constitute an exception to the axiom “nothing acts on itself” adduced by Gassendi in support of his objection that the thinker of the Meditations cannot know itself because, Gassendi argues, not only do corporeal entities or faculties not act on themselves (e.g., “the eye […] cannot see itself in itself”), but also “the intellect does not understand itself” (Fifth Set of Objections, AT 7, 292; CSM 2, 138).

Gassendi is right that no corporeal entities40 or faculties (brains or particles) can act on themselves, or know or cross-examine themselves, or have a first-person perspective. But he is wrong to conflate that with a thinking entity, a mind and its intellect. Gassendi’s conflation leads him to draw the erroneous conclusion, directed at Descartes, that there is “no hope of your knowing yourself” (AT 7, 292; CSM 2, 203).

Gassendi seems to be “one of those who think they cannot conceive a thing when they cannot imagine it, as if this were the only way we have of thinking and conceiving. […]” (letter to Mersenne, July 1641, AT 3, 393; CSMK, 185).

It is not possible to imagine [the mind] or form an image of it. But that does not make it any less conceivable; on the contrary, since it is by means of it that we conceive all other things, it is itself more conceivable on its own than all other things put together (letter to Mersenne, July 1641, AT 3, 393–94; CSMK, 185–86; italics added).

It is also unclear what Gassendi thinks the self-cross-examination of the First and Second Meditations amounts to, or how it is carried out.41 It is the thinker’s mind with its faculty of intellect which has the unique power to cross-examine itself, to know itself, to act on itself, constituting an exception to the axiom.

Equally importantly, Descartes distinguishes between the acts of thought and the content of such acts. The acts of thinking, doubting, perceiving, sensing, etc.—that is, that I am perceiving, sensing, etc.—cannot be doubted, but what I am perceiving can be doubted (Third Meditation, AT 7, 39; First Set of Replies, AT 7, 103; Third Set of Objections with Replies, AT 7, 176).42 This is clearly demonstrated in the First and Second Meditations, where he supposes:

I am now seeing light, hearing a noise, feeling heat. But I am asleep, so all this is false. Yet I certainly seem to see, to hear, and to be warmed. This cannot be false; what is called ‘having a sensory perception’ is strictly just this, and in this restricted sense of the term it is simply thinking (AT 7, 29; CSM 2, 19; Third Meditation, AT 7, 35; Sixth Meditation, AT 7, 77).

there is nothing entirely in our power except our thoughts, at least if you take the word ‘thought’ as I do to cover all the operations [acts] of the soul, so that not only meditations and acts of the will, but the activities of seeing and hearing and deciding […] so far as they depend on the soul are all thoughts [are acts under the attribute of thought] (letter to Reneri for Pollot, April/May 1638, AT 1, 36; CSMK, 97).

Descartes’ characterisation is more detailed than the Discourse where, referring to his third maxim, he states: “In general I would become accustomed to believing that nothing lies entirely within our power except our thoughts” (AT 6, 25; CSM 1, 123).

Pertinent to my present concerns in particular, but also to our current debates in general, is the fact that Descartes’ conception of the acts of thought and his distinction between the acts of thought and what the acts are about, anticipates Frege’s subjective/objective distinction.43 For both philosophers, an act of thought is not part of the content (par. 7.2 above).

Frege states: “By a thought I understand not the subjective performance of thinking but its objective content, which is capable of being the common property of several thinkers” (Frege 1948, 215, n. 5). Descartes states: the act of thinking, perceiving, inferring, judging, sensing, etc., is performed by a subject, it pertains to a subject,44 but the content of any act is objective,45 including the content of the cogito, which meets the objectivity requirement of truth and, in its special case, self-evidently so, graspable by any thinker who attentively follows the order of discovery (Second Set of Replies, AT 7, 155), “anyone who philosophizes in an orderly way” (Principles I:7 and 10, AT 8-a, 7 and 8; CSM 1, 195); each capable of understanding that it applies to itself but also to each of the others; each capable of conceiving any other thinkers, each capable of forming a clear conception of itself as one thinker among many in a single objective world, any one of whom can attentively follow and execute the same method of enquiry (Christofidou 2022).

All this manifests the objectivity and universality of content, and demonstrates that content is not determined by internal factors only, but (in part) by external objective factors, including truth-conditions.46 I say “in part” because the acts of thinking, perceiving, etc., pertain to the subject. There is a relation between a subject and the object perceived, be it an empirical object, an eternal truth, or a true and real essence; indeed, in the last case truth thrusts itself upon the attentive mind.

The self’s “I”–perspective invokes responsiveness to reasons, to normative principles, to modal reasoning directed towards what can objectively be the case. The fact that only his perspective can express—make known to the objective world—the self that he is, does not entail that his conception is self-contained. Descartes’ concern is not with post-Cartesian baggage and the perspective of consciousness. His concern is with what is performed by, and what pertains to, a subject: the authority and objectivity of reason, the autonomy of freedom of the will, the power of thinking, sensing, and acting.

Our conception of the self and conscientia—self-consciousness and self-knowledge—is bound up with the relation between self-identification and self-ascription, both of which concern first-person thoughts: “I”-thoughts. One is self-identifying and self-ascribing in cross-examining one’s opinions, prejudices, habits, etc., and in scrutinising what one is.

Self-identification is concerned with “I”-thoughts about oneself as oneself. The “object of an ‘I”-thought is its subject” (Evans 1982, 260). Is this a substantive or a linguistic claim? Does it constitute an adequate answer to the question “what am I?”

Self-identification involves an immunity to error through misidentification relative to “I,” and a peculiarly strong form of identification-free self-reference. In “I”-thoughts one is cognitively aware of oneself in a direct way: an unmediated identification-free self-reference (Evans 1982, 186–189). This strong peculiarity does not, however, entail that the referent is either a peculiar entity, a momentary entity, a non-entity, or an “empty, representation ‘I’ […] a subject of thoughts = X”47—as I shall demonstrate.

Self-ascription is concerned with the ascriptive component of “I”-thoughts as being in a certain way, that is, the self-ascription of properties and acts of the mind, of properties of the body, and those arising from their substantial union. This is crucial, for the possibility then arises that in self-conscious thoughts, more is involved in the total cognitive awareness than the states of one’s mind.

I have argued (in Christofidou 2000) that self-ascription involves a second immunity, which I called “immunity to error through misascription,”48 and discussed at length its relation to the immunity to error through misidentification, addressing the complexities arising therefrom. One central point is that in the vast literature in this area, self-ascription is subsumed under the immunity to error through misidentification. This has led leading philosophers, such as Shoemaker and Evans—whose invaluable work in this area set the debate in motion—to argue that in the self-ascription of bodily properties the immunity to error through misidentification relative to “I” is only circumstantial or non-absolute.

Strawson argues that immunity to error through misidentification applies to “both states of consciousness and corporeal characteristics” (Strawson 1959, 104; Strawson 1966, 165). This is true. But his explanation is that “I” “can be used without criteria of subject-identity and yet refer to the subject,” because the links between criterionless self-ascription and the third-person criteria “are not in practice severed.”

There are two problems. First, Strawson conflates the identification-free self-reference of “I,” with criterionless self-ascription. Secondly, Strawson’s claim that the immunity to error through misidentification applies to “both states of consciousness and corporeal characteristics” must be argued for, not simply “repeat the point that […] it is guaranteed by […] the ordinary practices well established among human beings” (at best relying on an implicit verificationism: Strawson 1994, 211). The defence that “I” is immune to error in referring to an embodied subject must be the conclusion of one’s enquiry in this area.

In contrast, the conception of the self as an embodied being is the outcome of my enquiry. My argument has been that the immunity to error through misidentification relative to “I” is absolute, whatever the self-ascriptive component. One reason for this is that self-identification is always presupposed by any possible self-ascription. On Descartes’ insight, the immunity to error relative to “I” is not simply guaranteed by the perpendicular pronoun, the logic of indexicals, the ordinary practices of humans, or “the ordinary ways of talking” (AT 7, 36; CSM 2, 21), but by an ontological underpinning: a real, thinking, acting subject. This has significant implications for the move from selfhood to personhood.

But first, an explanation, albeit brief, of the second immunity is required. This immunity occurs with “I”-thoughts whose self-ascriptive component involves the self-ascription of certain mental properties (cogitations of reason, e.g., thinking or doubting; and cogitations of reason mixed with the senses, e.g., feelings or sensations).

I say certain because the second immunity does not occur in all cases of mental self-ascription. In self-ascriptions such as “I am in pain,” there is no question, not only that it is I who is in pain (a result of the first immunity), but also that it is pain that I feel (a result of the second immunity). Such statements have a double immunity.

In cases of mental self-ascription such as “I am seeing a bird,” however, the second immunity might not hold. But the identification component remains immune to error through misidentification relative to “I” absolutely, since there is no question that I am seeing, even if what I am seeing might be subject to doubt.

The second immunity might also not hold in cases of bodily self-ascription. If, say, in a mirror I see a leg bleeding and think it is mine, but in fact it is another person’s leg, then I am mistaken in thinking that my leg is bleeding. That, however, is not a case of erroneously misidentifying myself, or my leg, but of misidentifying the leg that is bleeding, or the person whose leg is bleeding. My mistake is established by determining the ascriptive component, not the identification component which remains immune to error absolutely. This is not a trivial consequence of the use of language, or of Strawsonian ordinary practices among humans, but has its roots in the nature of “my whole self,” as Descartes argues, the embodied human being or person. The question of whether first-person statements can be subject to error in self-ascription depends on conscientia as self-knowledge, of finding truths about oneself as being in a certain way. But now we are in the realm of the immunity to error through misascription (for a detailed discussion see Christofidou 2000, part. 4).

What I should add to my discussion (Christofidou 2000) is that the second immunity holds in the self-ascription of all acts of the mind, intellectual and sensory, since one is indubitably and immediately aware of them while they are taking place, presupposing the unity of the mind, and in turn the unity and irreducibility of “the same I”: “Ego sum res cogitans […] et sentiens.” All acts of the mind have a double immunity. The self is the irreducible “anchoring point” (Shoemaker 1984, 18) of each thinker, safeguarding its unity and numerical identity to which any conception it can have of itself must refer (Second Meditation, AT 7, 25; Third Meditation, AT 7, 36; see Christofidou 2022), manifesting the connection “between its persistence and its existence, and between its existence and [however minimal its knowledge] the kind of thing that it is” (Wiggins 1980, 54–5).

“I”-thoughts make vivid the fact that the thinker’s continuity and numerical identity across time involves “no keeping track of the object from t to t1.” There is “no need for any skill or care (not to lose track of something) on the part of the subject” since “I”-thoughts do not form dynamic Fregean thoughts: there is no shifting from “I”-thoughts to “you”-thoughts or “it”-thoughts as one thinks of oneself over time, since they “could not be connected by expressing a single dynamic thought” (Evans 1981, 295; see Christofidou 2022).49 It is not merely that thinking cannot be conceived apart from a thinking subject, but more substantially that thinking, sensing, and acting are inseparable from the nature of the self, who is the source, not the outcome, of thoughts, freedom, and actions.

In self-identification one is conscius of oneself in a “primitive way,” as Frege argues—in an irreducible and unanalysable way (Frege 1967, 25–6). The Fregean sense (the mode of presentation) of the referring singular term “I” is entity-invoking, it directly picks out something in reality: the thinking acting sensing subject. This special, primitive or irreducible way of being conscius of the referent can be explained by the fact that in first-person reference, unlike any other kind of reference, there is no gap between the subject and the referent which needs to be filled by evidence or criteria of identification.50 In first-person reference the object of the “I”-thought is identical with the subject.

That’s the power of the Ego sum, ego existo: what is grasped is the basis, not a consequence of the signification of “I.” Yet, despite his insight, Descartes does not argue that the immunity to error through misidentification entails that I am either a bodily thing, or simply a thinking thing.51 Descartes does not argue, even in the Sixth Meditation, that the I or self is disembodied, only that it is logically possible (AT 7, 78)—clearly missed by many commentators and critics alike over the centuries.52

Two key points follow: first, the immunity to error through misidentification is straightforwardly caught up in the metaphysics of selfhood and personhood. In “I”-thoughts, self-identification is immune to error through misidentification relative to “I” simpliciter—whatever the self-ascriptive component. Secondly, the significant implication of all this is that the immunity to error through misidentification and the identification free-self-reference are guaranteed for both the self qua thinking I, and “my whole self”—the self substantially united with the body constituting a person (letters to Elisabeth, 21 May 1643, AT 3, 664; 28 June 1643, AT 3, 691; CSMK, 226).

The self of the Second Meditation is indubitably endowed with reason’s authority and objectivity, the will’s autonomy of freedom, and its inseparability from “I”-thoughts, conscientia, self-identification and self-ascription. It is a real, true, thinking and sentient being, even if its understanding of its nature is epistemic, not yet metaphysical. Such a conception, which begins in the Second Meditation, leads through the strict order of reasoning of clear and distinct discoveries, towards the conception of “my whole self” in the Sixth Meditation—a conception of an embodied self, an irreducible notion of personhood.

When Descartes reaches the Sixth Meditation, the most important root idea of personhood is that I am not “present in my body as a sailor is present in a ship, but I am […] intermingled [conjunctum] with it, so that I and my body form a unit” (AT 7, 82; CSM 2, 56; Discourse, AT 6, 59)—a unio substantialis “ordained by nature” (Optics, AT 6, 130; CSM 1, 167).

I have recently discussed at length the union and offered a metaphysical solution to the interaction between mind and the body (Christofidou 2019). Here I shall draw on what is relevant to my present purposes. The union of mind and the body is not the result of their interaction. Rather, their interaction presupposes their substantial union. This has significant implications for our current debates in this complex area of metaphysics, negating any historical distance.

In defending the substantial union, Descartes writes to Regius: “a human being is a true ens per se [a true entity in itself], and not an ens per accidens [accidental entity].” The mind and the human body are united, not by “the mere presence or proximity of one to another, but by a true substantial union” (letter to Regius, January 1642, AT 3, 493 and (508); CSMK, 206 and 209; December 1641, AT 3, 460–61).53 Descartes expresses the fact that the mind–body interaction cannot in any way, metaphysical, epistemic, or scientific, be the same as or compared to other entities whose interaction presupposes no union.

He writes to Elisabeth: “I think that we have hitherto confused the notion of the soul’s power to act on the body with the power one body has to act on another” (letter to Elisabeth, 21 May 1643, AT 3, 667; CSMK, 218). Similarly, to Gassendi:

when you try to compare the intermingling of mind and [the] body with the intermingling of two bodies, it is enough for me to reply that we should not set up any comparison between such things because they are quite different in kind (Fifth Set of Replies, AT 7, 390; CSM 2, 266),

though they are all subject to his single causal principle, which is neutral as to the causal relata (Third Meditation, AT 7, 40).

What is unique and marks that “difference in kind” is a metaphysical necessity: the presuppositionality of the substantial union, without which a human being would not be a human being: “a true mode of union, as everyone agrees, though nobody explains what this amounts to” (letter to Regius, January 1642, AT 3, 493 and (508); CSMK, 206 and 209).

What nobody has explained—then or now—is not only the truth of the substantial union, but its uniqueness. It is unique because innumerable causal interactions, body–body interactions, occur in the world without presupposing a union, a principle of true unity.

Therefore, no explanations of body–body causal interactions can be used either against Descartes or in defence of his bidirectional mind–body causal interactions, because the latter would not occur without the mind-body substantial union. The reason for this constraint is that without the substantial union we would not have experiences, sensations, pains, feelings, sense perceptions, etc. Nor would the mind “incline its will” to action (letter for [Arnauld], 29 July 1648, AT 5, 222; CSMK, 357).

Without the presupposition and uniqueness of the substantial union, we would be only detachedly aware of causal effects, like sailors in ships having simply “an explicit understanding of the facts” (Sixth Meditation, AT 7, 81; CSM 2, 56). But that is all contradicted by the irreducible and undeniable facts of self-conscious awareness. Epistemically or phenomenologically, the substantial union is the only way to understand how we are, and why we feel so intimately united with our bodies.

Metaphysically, however, the substantial union does not follow from our experience or first-person awareness of interaction: the union is presupposed by the interaction—a union that can be clearly grasped by the intellect (Christofidou 2019).

The metaphysics of the union or personhood can be given a two–fold defence. First, the union is not up to us or our theories because it “is not accidental to a human being, but essential, since a human being [a person] without it is not a human being” (letter to Regius, January 1642, AT 3, (508); CSMK, 209), whose true nature arises from the union, an irreducible unity per se.54 Secondly, a person is neither a physical, neurobiological particular, nor a disembodied mind or ego; a person is an irreducible, unanalysable true entity—neither a mind nor a body (Comments on a Certain Broadsheet, AT 8-b, 351).

Descartes, insightfully, turns past and present theories of mind–body interactions on their heads: there is no more profound unity than that of mind–body union presupposed by mind–body interactions. There is a clear parallel between the metaphysics of the substantial union and (a) the metaphysics of the unity of conscientia, and (b) the metaphysics of the unity of an irreducible self who is the metaphysical and explanatory ground of personhood.

Metaphysically, the substantial union is the only way to understand what we are as persons: embodied, thinking, acting agents in the spatiotemporal world, who take responsibility for our metaphysical, epistemic, scientific, and moral commitments, our acts and actions.

Drawing on Descartes’ metaphysics and on “Cartesianism and Beyond,” that is, on some parts of contemporary philosophy, I have offered a resolution to the controversy that surrounds conscientia, and provided a basis for a unified account of selfhood, conscientia, the first person, and personhood—an account which is philosophically the closest to Descartes’ insightful conception.

I have demonstrated that arguments in contemporary debates on the complexities of the self have tried to explain the immunity to error in first-person thoughts by—at best—explaining the first immunity, but have given us no grip on the second immunity. These arguments seem to share a mistaken premise that judgements involving the self-ascription of bodily properties can only be circumstantially or non-absolutely immune to error through misidentification relative to “I.” My arguments have exposed the mistaken premise that conceives the body as external to the thinking acting subject, a view that fails to appreciate the fact that there is unique substantial union presupposed by their interaction, as Descartes argues, constituting a person. This is important, for it helps bring home to us the fact that there is nothing in the use of “I” that forces upon us either a distinction between absolute and circumstantial immunity to error or, more seriously, an actual separation between the two components of our nature. Nor does it force upon us an actual disjunction: neither a physicalist, neurobiological conception, nor an idealist conception of what we are. We come to realise that we are substantially united, embodied, self-conscious beings, each of which has reason and reflection and can think of itself as itself, a thinking, acting, free being—a person, a true ens per se. A person, unlike any other entity in the world, acts not only in accordance with laws, but from a clear recognition of principles, under the idea of freedom.

Freedom in its internal relation to reason, the highest grade of freedom, is “the greatest good […] the supreme good […] the noblest thing we can have […] [and] seems to exempt us from being [God’s] subjects” (letter to Queen Christina, 20 November 1647, AT 5, 81–6; CSMK, 324–26). It clearly exempts us from being subjected to physicalism or neurobiologism. Freedom, in its highest grade, confers upon us autonomy, self-determination, and epistemic and moral responsibility, making us “in a special way the author[s] of [our] actions” (Principles I:37, AT 8-a, 18; CSM 1, 205).55

Boyle, Matthew. 2016. “Additive Theories of Rationality: A Critique.” European Journal of Philosophy 24 (3): 527–55.

Christofidou, Andrea. 2000. “Self-consciousness and the Double Immunity.” Philosophy 75 (294): 339–69.

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Christofidou, Andrea. 2019. “Descartes: A Metaphysical Solution to the Mind-Body Relation and the Intellect’s Clear and Distinct Conception of the Union.” Philosophy 94 (367): 87–114.

Christofidou, Andrea. 2021. “Human Rationality: Descartes and Aristotle.” Philosophical Investigations 44 (3): 217–36.

Christofidou, Andrea. 2022. “Descartes’s Flash of Insight: Freedom, the Objective World, and the Reality of the Self.” The European Legacy 37 (3–4): 251–68.

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1 A person is constituted by the substantial union of mind and the body. It is not identical with the union, which would violate the logic of identity, nor is it identical with either of them alone. Yet although Descartes uses “person” to refer to the mind-body composite, because the soul can be immortal, Thiel refers to the thesis that personal identity consists in the identity of the soul as the Cartesian view (Thiel 2012, 270). It is not clear which Cartesian view this is, but it is certainly contrary to Descartes’ commitments, as is evident throughout my discussion. Descartes’ metaphysics of mind needs to be divorced from so-called Cartesian philosophy of mind and Cartesianism, and be understood in itself.

3 This affinity is drawn out of Socrates’ preoccupation with self-examination and the method of elenchus, and of Plato’s concern with self-knowledge (see for example, the dialogues mentioned in n. 5).

4 It was one of three injunctions inscribed in the pronaos (forecourt) of the Temple of Apollo at Delphi.

6 See par. 4 below, and also, for example, Radner 1988, 439; Lähteenmäki 2007, 177–201; Simmons 2012.

7 I say “at least” because “self-consciousness” is also traceable after Descartes, to the early eighteenth century.

8 The cogito was discovered non-inferentially. However, if the discoverer has to give an explanation, a defence, or recapitulation of the cogito, he can do so only by means of an argument. How else can Descartes convince his critics of its truth, other than by providing forms of argument that they can understand, since they find his order of discovery difficult to grasp? See Christofidou 2013; for a more detailed discussion, Christofidou 2022.

9 Simmons (2012, 3), apparently unaware of this, claims that Descartes uses “the Latin conscius and conscientia by divesting the terms from their normative moral connotation […] and rendering them purely descriptive and psychological.”

13 After decades of scathing misattributions to Descartes of supposedly relying on introspection, in recent debates especially in the philosophy of mind, introspection has become the yardstick for distinguishing the mental from the physical. This moves fallaciously from introspective awareness to metaphysics.

14 Descartes discovered the marks of clarity and distinctness in his cross-examination of the cogito in the Second Meditation (AT 7, 25–7; CSM 2, 16–8), which withstood that scrutiny. He thus takes the withstanding of the rigorous scrutiny as the mark of clarity. The cogito is grasped or understood as indubitably true, without being dependent on or needing anything extraneous to; it is distinct from anything extraneous to it. Distinctness is thus established as the second mark of truth, both marks are necessary for whatever is true and indubitable. Following his strict order of reasoning, in the Third Meditation (AT 7, 35; CSM 2, 24), after going through the cross-examination once again, Descartes is able to lay down his principle of clarity and distinctness: “I now seem to be able to lay it down as a general rule that whatever I perceive very clearly and distinctly is true.” The “seem,” I have argued (in Christofidou 2013, chapter 4), is significant, demonstrating Descartes’ unrelenting cross-examination of what he is laying down; that is, he proceeds to cross-examine the principle before he establishes it. The Meditations and the Principles I:45 are consistent.

15 Leibniz criticises those “who misuse the principle that every clear and distinct conception is valid” (letter to Arnauld, 14 July 1686, Leibniz 1973, 63). The editor of Leibniz’s Philosophical Writings explains that Leibniz is attacking Descartes for such a misuse “because we need to know when an idea is clear and distinct” (Leibniz 1973, 63 n. 1). Leibniz seems to have missed Descartes’ explanation.

17 “Confused” (confundere) in Descartes’ use doesn’t mean bewildered or perplexed, as a number of commentators think, nor does he use “confused” and “obscure” interchangeably. “Confused” is contrasted with distinctness, “obscure” is contrasted with clarity; a sense-perception can be clear but cannot be distinct. See Christofidou 2013; Christofidou 2019; Christofidou 2022.

18 Descartes does not follow “the order of the subject-matter which is good only for those […] who can say as much about one difficulty as about another” at the same place (letter to Mersenne, 24 December 1640, AT 3, 266; CSMK, 163).

19 By “analysis” Descartes does not mean reduction. From the Greek verb analýo (ana can mean “through” and lýo unravel, loosen), it means to unravel, loosen, investigate, meditate, to examine closely in order to discover. Thus by “analysis” he means to discover through enquiry, through unravelling, through elucidating the complexities.

20 Descartes changed “must infallibly” to “must rather” in the Latin translation (1644) of his Discourse (Descartes 2006, 76, note 34). Sometimes he uses “infallible” when referring to those inclined towards divine revelation, which he rejects (Principles, Preface to the French edition, AT 8-a, 5; CSM 1, 181). In his letter to [Mesland], 2 May 1644, referring to theological controversies, he says, “we may earn merit even though, seeing very clearly what we must do, we do it infallibly [infalliblement], and without indifference” (AT 4, 117; CSMK, 234). “Infallibly” is used adverbially to mean inevitably or without fail: “the will [being at one with reason] is drawn voluntarily and freely […] but nevertheless inevitably [aliter, infallibiliter], towards a clearly known good” (axiom 7, AT 7, 166; CSM 2, 117).

21 Contemporary epistemologists have only recently began considering the relation between epistemic and moral normativity and virtue.

22 The emphasis on corporeal objects is important, even though in his later commitments concerning pure mathematics and pure geometry he abandoned the aid of imagination and diagrams and introduced his co-ordinates and algebraic equations.

25 Regarding the distinguishability of the self, see Christofidou 2022. Thiel states that Descartes did not give an account of the individuation of the soul: Thiel 2011, 38. Thiel perhaps did not realise that (as I argued in Christofidou 2022) for Descartes individuation is primitive; that is, for being an individual no condition is required other than sum and its inseparability from ens, denoting a true unity or indivision. A true unity is what makes individuation possible; it itself cannot presuppose individuation. The self, being one in itself, is an individual true unity. What is at issue is distinguishability. Individuation is prior to distinguishability.

26 Ryle 1949, 186. Having made this mistake, Hume was unable to find the looked-for self. Unlike Ryle and others, past and present, however, Hume had the intellectual honesty to admit in the Appendix that his bundle theory failed to account for the self and “the nature of the uniting principle, which constitutes a person” (Treatise I.iv.ii; Hume 1978, 189). Without the self, none of his theses could be sustained, or would make any sense.

27 In my article Descartes on Scepticism, Habits, Freedom and the Self, in progress.

29 Regarding “reflection” he writes: “When an adult feels something, and simultaneously perceives that he has not felt it before, I call this second perception reflection, and attribute it to the intellect alone, in spite of its being so linked to sensation that the two occur together and appear to be indistinguishable from each other” (letter for [Arnauld], 29 July 1648, AT 5, 221; CSMK, 357).

30 This phrase was introduced by Sellars as a criticism of the view that what we sensorily perceive can be independent of the conceptual processes which result in perception, and that such sensory experience gives us certainty suitable to serve as a foundation for the whole of empirical knowledge and science (Sellars 1956, 298–99). All this is contrary to Descartes’ metaphysical commitments which rely, first, on clear and distinct ideas of reason, and secondly, on Descartes’ view that the content of both intellectual acts and sensory acts is conceptual (see also Christofidou 2021).

31 See Hennig’s citations and discussions of such arguments (Henning 2007); also McRae 1972, 55–6, especially nn. 2 and 3.

32 “Substance,” “essence,” “attribute” don’t apply univocally to God and finite entities.

33 As I argue elsewhere (presented at the Princeton/Bucharest Seminars Autumn 2022), since these modes remain inseparable and unchanged while the thing exists, they can be called “attributes,” but non-essential, because they have no bearing on the essence of things (except existence pertaining to God’s essence).

34 This has far-reaching consequences for contemporary writers who attempt to ground consciousness, our rational and sensory acts, all severed from the mind, in the neurobiological or physical, or who claim that consciousness arises from a physical/biological basis. Yet, oddly they have no explanation of why and how it so arises, referred to as the explanatory gap, and dubbed “the hard problem of consciousness.” The gap is not simply explanatory but metaphysical.

35 For Descartes, “all men [homines] have the same natural light” by their very nature as reasoning beings. The difference between them can be traced to the fact that some allow it to be clouded by preconceived opinions and habits: “hardly anyone makes good use of that light [and therefore many] may share the same mistaken opinion” (letter to Mersenne, 16 October 1639, AT 1, 598; CSMK, 139. Principles I:50). Descartes’ use of the neutral homines (mistranslated as “men”) expresses his commitment to equality, long before we became sensitive to these issues. By “the natural light of reason” he is referring neither to anything physical nor to divine grace or supernatural illumination (he rejects both), but to something real and natural pertaining to any thinker. Whatever is physical might be real and natural, but it’s fallacious to infer that whatever is real and natural is physical.

36 Descartes is quite clear that it is of the operations or acts of the mind that we are immediately conscii at the moment when they are enacted. This contradicts what Simmons claims: that for Descartes “all and only thoughts are conscious.” She then proceeds to criticise him, stating: “today the idea that all thoughts are conscious seems obviously wrong” (Simmons 2012, 1). Radner also states: “it seems that Descartes is not only confused [regarding this point] but also committed to consequences detrimental to his system” (Radner 1988, 439).

37 What is mind-independent may be real, but it’s fallacious to infer that what is real is mind-independent. Our thoughts, feelings, etc., are real but are not mind-independent.

38 Mind and body are really distinct in their natures, which implies separability not actual separation, as we shall see in par. 10 and par. 11.

39 Boyle mistakenly aligns Descartes with the additivists (Boyle 2016). See Christofidou 2021.

40 Corporeal entities have powers to bring about an effect, to interact, to move, but not act on themselves.

41 I have argued elsewhere (Christofidou 2013, chapter 1), one of the reasons for postulating the demon is to provide a backdrop against which reason can enquire into itself, a task predicated on intense cross-examination. Descartes is not prepared simply to assume the authority of reason without good reasons, especially if he is to demonstrate, as against the denial by thinkers such as Gassendi (and predecessors such as Montaigne), that reason is capable of transcending appearances and clearly and distinctly grasping the nature of things.

42 He is neither a representationalist—he rejects the retina-image thesis (Optics)—nor an indirect realist. See Christofidou 2013.

44 Descartes doesn’t use the modern sense of “subjective” and hence couldn’t have “given birth to subjectivity”; as far as I know, he doesn’t even use the Latin adverb subjective, which meant what belongs to things, or as they are in themselves. During the course of its history, the Latin adverb came to have all the connotations associated with post-Cartesian baggage.

45 The “objective reality” of an act signifies what the act is about, the object, not the idea of it—a rejection of the veil-of-perception-thesis. See Christofidou 2013.

46 Whatever is physical might be objective, but it’s fallacious to infer that what is objective is physical. Objectivity encompasses far more than physicality.

47 Kant 1933, A346/B404 (Paralogisms). Kant intends this as a criticism of Descartes because he thinks that Descartes moves fallaciously from “I am thinking” to “I am a thinking thing,” as a metaphysical commitment. But this is a mistake. Following the order of reasoning, Descartes’ commitments in the Second Meditation are epistemic, not metaphysical; this is made clear at AT 7, 27 and the Preface, AT 7, 8—somehow missed by critics. Furthermore, the cogito establishes the indubitability of the meditator’s existence, not its existence, which would be nonsensical (see Christofidou 2013, chapters 2–3; Christofidou 2022).

48 Not to be confused with old-style incorrigibility (Christofidou 2000, part 5).

49 Thiel states that Descartes failed to given an account of the identity of the soul over time: Thiel 2011, 38. Evans’s account and my interpretation of it, provide an adequate response to this.

50 For a fuller discussion see Christofidou 2000; Christofidou 2013 chapters 2–3; Christofidou 2022.

51 Contra Strawson’s misattributions, labelled “the Cartesian illusion”: Strawson 1966, 163–74.

52 For drawing the real distinction between the nature of mind and body (corpus), it’s sufficient that I clearly and distinctly understand myself “in so far as I am simply a thinking thing” (without including imagination and sense perception, despite their being inseparable from my nature); and “on the other hand [that] I have a distinct idea of body, in so far as this is simply an extended […] thing” (AT 7, 78; CSM 2, 54; see also Christofidou 2013; Christofidou 2018).

53 Also letter to Elisabeth, 28 June 1643, AT 3, 691; Fourth Set of Replies, AT 7, 227–28.

54 This is consistent with the position that mind and body are really distinct in their nature and can exist without each other. For how one entity, a person, can be constituted by two substances (strictly, the human body is not a substance), see Christofidou 2013, 221–26.

55 I should like to thank Andrea Strazzoni and Marco Sgarbi for organising a series of seminars on Cartesianism and Beyond, in March–June 2022, which I attended and, as a consequence, for inviting me to contribute to this special edition of a collective volume related to the seminars. I should also like to thank Peter J. King for his valuable comments and numerous discussions.

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