自我與現象意識

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行政院國家科學委員會專題研究計畫成果報告

自我與現象意識(第 3 年)

研究成果報告(完整版)

計畫類別：個別型計畫編號： NSC 97-2410-H-004-154-MY3 執行期間： 99 年 08 月 01 日至 100 年 09 月 30 日執行單位：國立政治大學英國語文學系計畫主持人：藍亭計畫參與人員：碩士班研究生-兼任助理人員：薛旭任碩士班研究生-兼任助理人員：張哲虹碩士班研究生-兼任助理人員：張凱琪碩士班研究生-兼任助理人員：蘇偉誠碩士班研究生-兼任助理人員：周映妤大專生-兼任助理人員：黃品嘉大專生-兼任助理人員：呂懷哲博士班研究生-兼任助理人員：周怡岑博士班研究生-兼任助理人員：沈映伶報告附件：出席國際會議研究心得報告及發表論文公開資訊：本計畫可公開查詢

中華民國 100 年 12 月 30 日

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中文摘要：在心理學、神經科學尚未發展的六○年代，哲學家要研究心理或心靈，僅能透過內省或純思考方式。美國哲學家 Sydney Shoemaker 在 1968 年提出「IEM（immunity to error

through misidentification）」學說，他認為當「我」做為主體，只要透過內省來感知痛覺、觸覺等感官經驗，那必然是「我」的感受，不可能辨識錯誤。例如當一個人說自己牙痛的時候，我們並不會質疑對方「那真的是你的痛覺嗎？」此外，Shoemaker 主張此關係不僅維持我們的體感經驗，同時也作用於行動意識與視覺感知。然而，本研究透過實際病例與實驗結果，證明此關係並非必然。以研究病患症狀為例，某些病患會將自己的肢體視為「他人的」，而產生主體與意識經驗的分離。舉例而言，某病患將自己的左手視為外甥女，實驗設計反覆觸碰其左手，當病患被告知其左手要被觸碰時，她表示並無感覺，只有當實驗者告知她「外甥女的左手要被觸碰了」，病患才有觸覺反應。此病例說明雖然「我」是主體，卻必須將意識經驗表徵為「他人的」，才能透過內省去體驗並恢復感知。本研究以此成功推翻了長年以來廣為接受的 Shoemaker 學說（IEM），認為其學說僅能視為「假說」，並非任何情況下都能成立。本研究旨在以心理學、神經科學等研究方法來檢驗哲學問題，並期望達成以下目標：(1) 透過告知臨床醫生哪些問題應被問及，協助醫生更了解病患情況；(2) 設計實驗使我們更了解「自我」、「意識經驗」與「身體」之間的關係。中文關鍵詞：自我,意識,心智歸屬,體化,自然主義,神經哲學

英文摘要： The main contribution of my research over the past three years has been to show that conscious

experiences can sometimes only occur if they are represented as belonging to someone other than self. The standard assumption is that when we

introspectively know that a state like pain exists, we necessarily know that it is our pain. Most

philosophers take this to be a tautology, a conceptual truth, or a datum. The most well-know articulation of this relationship between conscious states and self is Sydney Shoemaker‘s ’immunity to error through misidentification relative to the

first-person pronoun’ (’IEM’). David Rosenthal has also developed a version of this principle, which he calls ’thin immunity.’ In a series of essays I have

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argued that immunity principles should be regarded as hypotheses. Moreover, by adducing evidence from

various pathological states (Anton‘s Syndrome, Somatoparaphrenia, and Thought Insertion) as well as evidence from certain experimentally-induced

illusions (the Rubber Hand Illusion and Full-Body Illusions) I have shown that IEM or IEM-like hypotheses are confronted by genuine counter-examples. First-person awareness that a conscious state is instantiated does not entail awareness that it is instantiated in oneself.

英文關鍵詞： Self, Consciousness, Mental Ownership, Embodiment, Naturalism, Neurophilosophy

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!" Table of content Chinese Abstract."##################################################################################################################################"$! English Abstract."##################################################################################################################################"$! Key Words."#############################################################################################################################################"%! Project Content:"####################################################################################################################################"%! Preface"############################################################################################################################################"%! Research Purpose."######################################################################################################################"&! Literature Review."######################################################################################################################"&! Methodology."#############################################################################################################################"!&! Results and Discussion, Part I: Self-Consciousness"#####################################################"$!! Self-Consciousness and Immunity"############################################################################"$!! Mental Ownership and Higher-Order Thought"#####################################################"&%! Higher-Order Thought and Pathological Self"########################################################"&'! A soft self and a hard core."##########################################################################################"(&! Results and Discussion, Part II: Sleep Mentation"######################################################"))!

The threshold of wakefulness, the experience of control, and theory

development."####################################################################################################################"))! What subjective experiences determine the perception of falling asleep during sleep onset period.1. Introduction"###############################################################")*! Results and Discussion, Part III: Belief and Ethics"###################################################"'$! The ethics of false belief."#############################################################################################"'$! Results and Discussion, Part IV: Anti-Individualism and Vision Science. "############################################################################################################################################"!!!! Results and Discussion, Part V: Partial and Whole Body Illusions."#################"!!$! The malleability of self and body experiences."#################################################"!!$! Self-specificity and mineness."#################################################################################"!!$! Mental ownership and the rubber hand illusion."###############################################"!!(! Results and Discussion, Part VI: The ethics of suicide research."##########################"!!(!

Media Impact on Individual Suicidality-A proposal for an ethical

neuroimaging study"#####################################################################################################"!!(! Acknowledgments"#################################################################################################################"!!)! References"################################################################################################################################"!!)! Self-evaluation of project outcome"###########################################################################################"!%!!

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1. Chinese Abstract

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The main contribution of my research over the past three years has been to show that conscious experiences can sometimes only occur if they are represented as belonging to someone other than self. The standard assumption is that when we introspectively know that a state like pain exists, we necessarily know that it is our pain. Most philosophers take this to be a tautology, a conceptual truth, or a datum. The most well-know articulation of this relationship between conscious states and self is Sydney Shoemaker's “immunity to error through misidentification relative to the

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first-person pronoun” (“IEM”). David Rosenthal has also developed a version of this principle, which he calls “thin immunity.” In a series of essays I have argued that immunity principles should be regarded as hypotheses. Moreover, by adducing evidence from various pathological states (Anton's Syndrome, Somatoparaphrenia, and Thought Insertion) as well as evidence from certain experimentally-induced illusions (the Rubber Hand Illusion and Full-Body Illusions) I have shown that IEM or IEM-like hypotheses are confronted by genuine counter-examples. First-person awareness that a conscious state is instantiated does not entail awareness that it is instantiated in oneself.

3. Key Words

Self, Consciousness, Mental Ownership, Embodiment, Naturalism,

Neurophilosophy

4. Project Content

A. Preface

This project holds out the promise of clarifying what kind of thing or process we are (i.e. what a self is)—in other words, that which is most distinctive about human beings—of what or whom gets lost in dementia, and with what or whom we are communicating when we converse with those suffering from PVS. We live on an island inhabited by thousands of PVS patients. But we have no way to reach out to them. I hope we can provide a way, a way that can then be applied to PVS patients in other parts of the world. Conceptual breakthroughs and new technology are making this possible. As a moral community we would be remiss were we to ignore this chance to communicate with those among us who are most isolated.

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B. Research Purpose

(1) Theory-related purpose: sometimes conceptual arguments can take hold with such force that they become impediments to intellectual inquiry. I believe that this has been the case with immunity principles. The intent has been to remove this impediment—the immunity principles—to intellectual inquiry, by promoting an inter-animation of philosophical theory and empirical inquiry.

(2) Practical purpose: One, among many reasons, for pursuing this line of research, is to increase our understanding of standard conditions for the normal sense of self and its embodiment. By enhancing our understanding of embodiment in normal conditions, we can better project how this sense would vary under atypical circumstances, such as what might be experienced during periods of acceleration or deceleration, during periods of weightlessness, or when functioning at high altitudes.

(3) By extension from point we can better train those who rely upon prostheses or who work with tools in atypical environments. For the former, we would be enhancing their efficiency and their safety; for the latter, their quality of life.

C. Literature Review

1. Some Background:

The main purpose of this three-year project is to develop an idea that I first formally proposed last year, Mental Ownership Theory. This idea, however, has been percolating for several years. Mental Ownership Theory (MOT) concerns how we distinguish between mental states that belong to self and mental states that belong to others. I can know that a mental state (e.g. fear) exists, by “seeing” it in the eyes of a person standing before me; I can also know that fear exists via introspection. Under normal circumstances, in the former case we reliably attribute fear to someone else and, in the latter case, attribute it to self. This very natural tendency has led many philosophers and scientists to think that the difference between attributing fear to self and fear to others is strictly determined

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by the mode-of-access: one via perception of something observable in the external world; the other, via something that can be known, “directly”, via introspection. But I (Lane and Liang 2009, 2010, 2011) have already demonstrated that the

access-distinction—to a first approximation, introspection versus perception of the

external world—is neither necessary nor sufficient for determining the self-other, the ownership-distinction. Mode-of-access is one among multiple factors that contribute to determining the belongingness of mental states.

Naturally, my point is not to deny that mode-of-access is highly relevant to determining ownership. But mode-of-access is not the determining factor. Were access not highly reliable in this respect, mobile creatures capable of mental states could not exist. Were we chronically confused about whether, say, body sensations belong to me, to someone else, or to no one, then it would be difficult to imagine circumstances that would allow for the existence of our species. If pain, or fear, or the visual experience of a rapidly approaching projectile exists, it is critical to know whether these belong to self or to someone else. In the former case, we had best be prepared to act. In the latter case, a more relaxed approach can be adopted—after all, it is not me who is in harm’s way.

It turns out to be the case that mode-of-access and ownership are just contingently related. This claim is highly counter-intuitive for most, if not all, people. The standard intuition is well articulated by Wittgenstein’s (1958: 66-67) famous rhetorical question: “…there is no question of recognizing a person when I say I have toothache (sic). To ask ‘are you sure it is you who have pains?’ would be nonsensical.” This intuition was then developed by many, most famously Shoemaker (1968).

Shoemaker (1996: 10) proclaimed that the relationship between a subject and an experience are as intimate as a “branch and a branch bending”: the “bending” cannot exist independently of the “branch.” Concepts of the relevant sort are tautologically (Shoemaker 1968: 563-564) related to one another, such that when we make a judgment like “I feel pain” we are aware that “one does, oneself, feel pain…one is, tautologically, aware, not simply that the attribute feel(s) pain instantiated, but that it is instantiated in oneself.” It “cannot happen that I am mistaken in saying ‘I feel pain’ because, although I do know of someone that feels pain, I am mistaken in thinking that person to be myself” (Shoemaker 1968: 557).

Cast in more formal terms, Shoemaker says of what he terms immunity to error “through misidentification relative to the first-person pronouns” (IEM) that

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to claim that a statement “a is !” might be erroneous through misidentification relative to the term “a” is to allow for the following possibility: “the speaker knows some particular thing to be!, but makes the mistake of asserting ‘a is!’ because, and only because, he mistakenly thinks that the thing he knows to be!is what ‘a’ refers to.” But if Shoemaker has accurately identified a tautology, then mistakes of this type are not possible. Assuming that the ground of my judgment is introspection, whenever I say “I feel pain” it cannot be the case that I am mistaken in thinking that the person in pain is me.

Despite what strikes many—perhaps all of us—as a tautological relationship between concepts, it seems we are easily misled by analogies like “branch bending” and “branch.” It is the case that “bending” cannot occur without a “branch,” or some other similarly pliable object. But the relationship between a self (or a subject) and a mental state is importantly disanalogous to Shoemaker’s example. Although mental states do require brains (or some suitable brain substitute) to exist, it does not follow that a self and a mental state are related in the same way as “branch” and “bending.” As familiar cases of thought-insertion reveal (Stephens and Graham 2003), selves can be seriously confused as regards their relationship to mental states that are available to them via introspection.

During the first stage of developing MOT I have not, however, devoted much attention to thought-insertion. One reason for postponing treatment of thought-insertion is that during stage one I wanted first to expose the inadequacy of IEM and Gallagher (2000), along with others (e.g. Coliva 2000a and 200b), have previously defended IEM against objections raised that are based upon the conscious experiences of schizophrenics. Gallagher’s (2000: 231) main point is that a patient in a florid schizophrenic state claims only that he is not the “author” of thoughts; hence, they are felt to have been “inserted”. I do address Gallagher’s concerns (Lane and Liang, Forthcoming), but I began making the case against IEM with reference to a pathology of a different sort—somatoparaphrenia.

2. Somatoparaphrenia and IEM:

My first attempt to address the issue of immunity was not directly motivated by Shoemaker’s IEM. Instead, (Lane and Liang 2009 and 2010) it was motivated by a different version of immunity, one promulgated by Rosenthal, what he terms “thin” immunity (2002, 2004: 168-176 and 2005: 341-353). That was an extension of a more general critique (Lane and Liang 2008) of what Rosenthal

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regards as an empirical theory of consciousness, Higher-Order Thought (HOT). But some aspects of MOT were developed while addressing a component of HOT—thin immunity—and while responding to Rosenthal’s (2010) defense of thin immunity against my criticisms. Here, however, I will concentrate just on those aspects that address the more well-known version of immunity, Shoemaker’s IEM. In both cases though, both IEM and thin immunity, the point of departure is a complex phenomenon, somatoparaphrenia.

Somatoparaphrenia (Vallar and Ronchi 2009) is a syndrome that is characterized by the sense of profound estrangement from parts of one’s body. It is typically found in patients who have suffered extensive right-hemisphere lesions (usually vascular). Lesions in the temporo-parietal junction are a common neural correlate of somatoparaphrenia, but deep cortical regions (e.g. the posterior insula) and subcortical regions (e.g. the basal ganglia) are also sometimes implicated. Somatoparaphrenia is also closely associated with proprioceptive impairment and often (not always) co-morbid with hemispatial neglect. Patients feel that a contralesional limb, most frequently the hand, seems not to belong to them; indeed, it often seems to belong to someone in particular, not uncommonly an acquaintance. The sense of disownership can be so vivid that even after recovery patients continue to describe the estrangement in factive, not metaphoric, language (Halligan 1995).

Somatoparaphenia is occasionally accompanied not only by

hemispatialneglect, it is also accompanied by tactile extinction (the loss of conscious tactile perception) in the estranged body part. Moro et al. (2004) demonstrated (for two cases) that by merely changing the position of the hands—moving the left hand across the midline of the body, over to the right-hand side—tactile sensation could be recovered. Even though tactile sensation could be so readily recovered, the sense of limb disownership was unchanged.

As regards my challenge to IEM, the most relevant case has been described by Bottini et al. (2002). A woman (FB) reported that her left hand belonged to her niece and that she (FB) felt no tactile sensations there. In FB’s case the lesion was subcortical, involving the basal ganglia, white matter underlying the insula, as well as other areas. But, importantly, the primary somatosensory area—which is critical to processing tactile sensation—was preserved. As Bottini et al (2002: 251) record: “F.B.’s spared ability to perceive tactile stimuli, provided that these were

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referred to someone else’s body, was evidently based on the survival of some elementary somatosensory cortical functions.”

In a series of controlled tests, FB, while blindfolded, was advised that the examiner would touch her left hand; next the examiner would in fact touch the dorsal surface of FB’s hand. Whenever this was done, FB said that she could feel no tactile sensations. When advised that the examiner was about to touch her

niece’s hand, however, upon actually being touched, she reported feeling tactile

sensation. It is here that we begin to see the relevance of FB’s case to IEM.

It should be born in mind that FB was in all other aspects cognitively sound. Moreover, in order to ensure that these tests would be reliable, catch trials—wherein FB was led to expect touches that were not forthcoming—were used. These trials were evenly distributed across three verbal warnings—I am going to touch your right hand, your left hand, and your niece’s hand—and were administered in four sessions, two on one day, two on the next. It is of paramount importance to note that in not even one of 36 catch trials, 9 each per session, did FB respond incorrectly. In other words, when advised that she (or her “niece”) would be touched, if no contact was made, FB always reported “no,” no contact had been made.

When reflecting upon IEM in light of Bottini et al.’s findings, I allowed that most of Shoemaker’s views as regards self, mental states, and conscious experience are true. But even when assuming (for the sake of argument) that Shoemaker’s principal theses are true, we are left with an explanatory puzzle: why is it that when FB is expecting to be touched (on the left hand), she feels nothing, whereas when she expects that her niece will be touched there, she is able to report tactile sensation? Why, despite the experimental controls that are in place (e.g. blindfold and catch trials), is she able to judge that “her niece” has been touched? Typically to say (a) “I am going to touch your arm,” implies (b) “I am going to touch you.” It would be nonsensical to say (a) without implying (b). Likewise, when the doctor says “I am going to touch your niece’s hand,” she implies that “I am going to touch your niece.” The concern here is not about where the sensation will be felt, but about who will feel the sensation. Pace the prototypical situations that motivate the Wittgenstein-Shoemaker intuition—it is

not absurd to inquire as to whom is the subject of experience.

If we divide the experiment into two parts: FB expecting that she will be touched is Part 1 and FB expecting that her niece will be touched is Part 2. FB’s

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case should be regarded as directly relevant to IEM because she has been primed by the doctor to introspect. I argue that in Part 2 FB is misrepresenting her tactile sensation as belonging to someone else. In Part 2, from FB’s first-person perspective, when introspecting on that tactile sensation, FB is misrepresenting herself, such that she is not the owner of the sensation. In a word, FB commits an error through misidentification regarding just who is the subject of the sensation.

It is then empirically possible for a subject, while introspecting a mental state (and thereby knowing that someone is undergoing that state), to be in error with regard to whom is experiencing that particular mental state. Admittedly this is counterintuitive. The Wittgenstein-Shoemaker intuition that to inquire of the person who introspects and reports a toothache whether it is indeed that person who has the ache strikes all of us as absurd. But empirical inquiry has ways of upsetting the apple cart: it would by no means be absurd to ask of FB whether it is she who has the tactile sensations, even though it is she who produces the introspectively-based report.

Notice that there is an important contrast here that calls for an explanation. We have a fact and a foil, the contrast between the two parts of FB’s case. In Part 1 when FB is primed to introspect on what she experiences, she reports nothing; in Part 2, when she is primed to introspect on what her niece experiences, she reports tactile sensation.

To ignore this difference would be to ignore a significant explanatory problem. Because FB Parts 1 and 2 have similar histories, it is possible to ask sensible contrastive questions, questions which enable us to elicit causal differences (Lipton 1993: 217-219). And this is a possibility that is not permitted by IEM. In this case the essential difference between the two is whether FB represents herself as subject of the mental state. This issue, concerning first-person representation of just who the subject is, I refer to as mental ownership.

One might worry that FB merely reports feeling the sensation, when in fact she does not feel anything. But on this series of tests had there been no actual sensations, the reports would not have been made. First, recall that in FB’s case the lesion was subcortical; her somatosensory cortex was preserved. So it is not surprising that she retained the capacity for experiencing tactile sensations. Second, FB’s performance on catch trials was perfect. Included among the catch trials were instances for which she was told that her niece’s hand was about to be touched, when in fact it was not touched. In these trials she never once made a

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false report—neither on the first nor the second day of the experiments. Third, other standard procedures were in place to monitor FB’s sustained attention and reliability of response: for example, FB’s hand was touched in a randomized, fixed sequence, which was repeated in four sessions, on two separate days. Therefore, because she was blindfolded and because of the other controls that were in place, she could only have given an accurate report had she actually experienced the sensation of being touched.

Moreover, imaging studies of self-referential processing show that there is no reason to suspect that problems pertaining to mental ownership typically impair tactile processing. Northoff et al.’s (2006) analysis of many and varied studies that engage the “feeling of mineness” indicates that these experiences are subsumed by a set of commonly activated regions within the cortical midline structure (CMS), regions that do not include the somatosensory cortex. More specifically, as regards somatoparaphrenia, Feinberg et al. (2010), in a detailed study of 13 patients who had been examined by brain imaging techniques within one week of acute hospitalization, identified a pattern of lesions distinctive of those who exhibited its clearest symptoms—repeated, refractory expressions of the conviction that their limbs belonged to someone else. In this study, the region found to be most distinctive was not the somatosensory cortex; rather it was the orbitomedial frontal cortex. The claim here is not that any one region of the brain plays an exclusive, causal role in the etiology of somatoparaphrenia. The claim is that there is no empirical reason to suppose that what underlies the

distinctive phenomenology of somatoparaphreia necessarily involves

incapacitation of areas critical to somatosensory processing.

The only reason left to suspect that FB might not actually have experienced the sensations would be the worry that her case is analogous to blindsight. In the case of numbsense (Palliard et al. 1983, Gallace and Spence 2008, and Rossetti et al. 2005)—also referred to as “blindtouch”—although subjects lack conscious tactile experience, they are to some degree capable of non-consciously processing tactile information. In other words, perhaps FB was informationally-sensitive to being touched but not experientially-sensitive to being touched. But FB’s case could not have been an instance of numbsense.

For one thing, well-studied cases of numbsense involve damage to the primary somatosensory areas, very much unlike the case of FB. More importantly, in cases of numbsense the ability to make verbal report is lost. The reason given

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for ascribing numbsense is that the patients are able to point, with a moderate degree of accuracy, to the place where they were touched. In other words, by analogy to blindsight, their success at guessing based upon non-conscious information, is indicated by pointing, not by verbal report. FB’s case is clearly not like this, since her capacity for verbal report is well-preserved.

I conclude that we are not immune-to-error in the way that IEM indicates. FB’s introspections give rise to puzzling responses, responses that are not compatible with IEM. Shoemaker’s (1996: 273) critical mistake might have been to infer from “what can happen as a matter of course,” to what must necessarily be true of introspection and mental states.

3. Mental states are only contingently related to belongingness: knowing-that a mental-state exists is distinct from knowing-to-whom it belongs:

Zahn et al. (2008) report the case of a 23 year-old male (DP) who complained of “double visions.” DP sought medical treatment for this problem five weeks after their acute onset. The “double visions” had begun while he was taking a long-distance flight, during which he experienced tachycardia, shortness of breath, and a fear of asphyxiation.

It was soon established that he does not literally experience double-vision. In fact when looking at a new object he sees it as a single object. But something had changed. According to DP (Zahn et al. 2008, 398), “he was able to see everything normally, but that he did not immediately recognize that he was the one who perceives and that he needed a second step to become aware that he himself was the one who perceives the object.”

In most other respects DP appeared healthy: for example, the second step was not necessary when initiating actions or when perceiving the actions of others. He seemed not to have passive experiences of his body, changes in body image, memory problems, delusions of control, thought insertions, obsessions, or compulsions. He performed well on a wide range of examinations that included tests for lexical retrieval, for visual object recognition, for attention or executive deficits, and for short-term, working, semantic and episodic memory. Moreover, his medical history contained no indication of psychosocial stress or trauma. Indeed, he seemed socially well-adjusted and capable of managing daily activities. The only other symptom was distress caused by the “double visions.” A follow-up exam one year after the initial presentation revealed that the “double visions” continued unabated.

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The apparent cause of this condition is hypometabolism, problems pertaining to the supply of or ability to metabolize glucose. In DP hypometabolism was found in right inferior temporal, parieto-occipital and precentral regions. Since “double visions” were restricted to visual object recognition, it is not surprising that the right inferior temporal and parieto-occipital regions were involved, as they are known to be critical to visual object and visuospatial recognition. The former is necessary for the representation of objects as part of the ventral visual “what” stream; the latter, part of the dorsal visual “where” stream.

4. Intimations of the Principles-of-Ownership: Pain Asymbolia, Visual-Tactile Synesthesia, and Empathy

Some states that we know via introspection feel as though they belong to others. Pain asymbolia (Aydede and Guzeldere 2002: 272-275, Lane 2008: 151-153 and Sierra 2009: 150) can help to illustrate this point, for some patients describe their pains thus: “I feel pains in my chest, but they seem to belong to someone else, not to me.” What appears to have happened in such cases is that patients retain the capacity for making sensory discriminations but lack the usual affective responses. The reason the two can dissociate is that sensory discrimination is subserved by a lateral pathway that terminates in the somatosensory cortex, while affect and motivation are subserved by a medial pathway (connected to insular and cingulated cortices as well as to limbic structures). Here, to use Carruther’s (2000: 206) felicitous phrase, the patient “floats above” the pains.

On the other hand, some states that we know of via perception of the external world can, in a qualified sense, feel as though they belong to self. Visual-tactile synesthesia can serve as an example. Synesthesia is a phenomenon wherein the stimulation of one sensory modality evokes the simultaneous subjective experience of sensation in another; perhaps the most common of which is grapheme-color synesthesia, the perceiving of numbers or letters as inherently colored (Robertson and Sagive 2004). But synesthesia takes many forms, including one for which the mere visual perception of another person being touched on the face or neck is experienced as tactile stimulation on one’s own face or neck (Blakemore et al. 2005). One subject claims to have always “perceived observed touch on other people as touch to her own body” (Blakemore et al. 2005: 1573); indeed, she was surprised to learn that the experience of feeling touches applied to other people is not commonplace. In this case the neural mechanism in

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virtue of she “felt” the tactile sensations of people she observes in the world seems to be caused by a neural substrate in which her “mirror system”—something which we all have—was overactive, in particular her somatosensory, pre-motor, and anterior insula cortices.

Both pain asymbolia and visual-tactile synesthesia are rare. But other phenomena which help to show how it is we attribute ownership are quotidian, in particular, empathy, our capacity for understanding how others feel. Here we can study, in experimental contexts, what is shared when we know that a mental exists in others and when we know that a mental exists in self. Likewise, we can study what is not shared. For example, Ochsner et al. (2008) compared the direct application of noxious stimuli to the viewing of video clips wherein persons underwent accidental injuries (e.g. leg or arm breaks). They discovered that when self experienced pain, a large portion of the mid insula and a portion of the middle frontal gyrus were uniquely activated. When viewing the video clips of others experiencing pain, the premotor and superior parietal cortex (implicated in shifting attention or perspective-taking) as well as three regions implicated in memory and affective learning (the rostralateral prefrontal cortex, the medial orbitofrontal corext, and the amygdala) were uniquely activated. But whether noxious stimuli are applied to self or whether one witnesses injury to others, the anterior cingulated cortex and the anterior insula are highly active.

The point of these examples is not to illustrate that people are confused about ownership. In the case of pain asymbolia, it just doesn’t feel as though it belongs to self. In visual-tactile synaesthesia, subjects know (or can easily infer) that someone else is also feeling a sensation of touch—independently of the tactile sensation that they feel. And, in standard cases of empathy, we are not confused. In an important, but qualified, sense, we do feel what others feel. But we still make appropriate self-other distinctions.

Nevertheless, these phenomena do show three things: (a) pain asymbolia shows that affect and a particular pattern of brain activity might play a role in precipitating a feeling or rendering a judgment as regards ownership. (b) Visual-tactile synaesthesia shows that observation of that which is external to self can be sufficient to induce, if not a numerically identical sensation, at least a sensation of the same type in the observer. And, (c) empathy, precisely because it enables us to study that which overlaps and that which does not, shows that, at least in principle, we could appropriately modulate the non-overlapping

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mechanisms so to induce ownership where otherwise itwould not obtain. Collectively, these are just three intimations, three clues or points of entry, to teasing apart the recognition of a mental state’s existence from the sense of to whom it belongs.

D. Methodology

1. Introduction: collaborations among philosophers and neuroscientists

Ever since the publication of Patricia Churchland’s (1987) Neurophilosophy, collaboration between philosophers and neuroscientists has become frequent. In some instances these collaborations result in the writing of neuroscience-informed manuscripts as, for example, Patricia Churchland’s (e.g. 1998: 231-254) work on Antonio Damasio, or Owen Flanagan’s (e.g. 1996: 32-52) work on Alan Hobson. But often the works are more fully collaborative, especially as involves research into the problems of self-consciousness and related subject matter. Representative of these collaborations are Daniel Dennett and Marcel Kinsbourne (1992), Olaf Blanke and Thomas Metzinger (e.g. 2008), Shaun Gallagher and Anthony Marcel (1999), Patricia Churchland and Terrence Sejnowski (1992), Frederique de Vignemont and Patrick Haggard (e.g. Kammers, de Vignemont, and Haggard 2010), Walter Sinnott-Armstrong and Michael Gazzaniga (Sinnott-Armstrong et al. 2008), to name just a few. In these instances philosophical concepts are often employed so as to inform experimental design and clinical investigations, and empirical findings can be so employed as to reshape, revise, and refine philosophical concepts. My focus is on the cultivation of just such fruitful interaction.

G ( í +M ä , - has explicitly acknowledged the importance of

interdisciplinary work of this type by allocating funds for the purchase of fMRI equipment to GÌ./0$+M GÌ120$+Mand GÌﬂ‡0$. One important intent of this funding is to promote research on issues relevant to traditional philosophical concerns. The nature of self, conscious experience, and the relationship between these is just such a concern: one that has long preoccupied philosophers, yet one that is now, just beginning to become empirically tractable.

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Sellars (1963: 2) once famously pronounced that “the aim of philosophy, abstractly formulated, is to understand how things in the broadest possible sense of the term hang together in the broadest possible sense of the term.” Those neuroscientists and psychologists who are prone to reflection on philosophy of science have often noted that too much experimental work is nothing more than just “a game played by its own rules on an isolated playground” (Wackermann 2006). My hope here is to chart a middle course, to meet in the middle: I am not, at this stage, aiming for the “broadest possible sense” in virtue of which things might be said to hang together. I am, however, aiming to collaborate with cognitive neuroscientists, so to find a middle way—something that anchors the abstractions, without allowing them to be confined to “an isolated playground.” MOT is an effort to show how results from diverse fields of study can “hang together.” One contribution that philosophy can make to cognitive neuroscience is the promotion of a synoptic view, what Wackerman aptly refers to as “a beautiful linking of facts.”If this research program proves successful, it will show how certain pathologies of consciousness, certain illusions, certain dissociative states, certain forms of sleep mentation, etc. are related to one another, how they “hang together.” The next step—three years hence, beginning in 2014—then would be to seek an abstract formulation of the scope that Sellars’ definition is intended to express.

3. Philosophical concerns and prediction:

Not without reservation, but to a considerable degree, I endorse many of Quine’s views. Although I cannot claim to be a Quine scholar, I take it that an important aspect of his philosophical views is that our theories must be grounded in prediction. The point is not of course that the main work of philosophers is, necessarily, to be in the business of producing testable hypotheses. On the contrary, “we believe many things because they fit smoothly by analogy, or they symmetrize and simplify the overall design” (Quine 1995: 256). But, in the same passage, while trying to make it clear that such attempts at fitting things into an overall design are not mere “idle fancy,” Quine (1995: 256) adds that our beliefs generate “every here and there, a hypothesis that can indeed be tested.”

A focus of this three-year project is to seek out some of those aspects of theory—in this case, MOT—which fall into the category of “every here and there.” Much of the motivation, as with the prior work on Shoemaker and Rosenthal, derives from philosophical, largely a priori theorizing. But, wherever possible, I

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am looking for opportunities to make explicit links, links that can help inform experimental and clinical science in the production of hypotheses that “can indeed be tested.”

4. A priori assumptions and the choice of methodology:

In his commentary on a project conducted by C. M. Yang, myself, and the Sleep Lab team at NCCU (Yang et al. 2010), Wackermann (2010: 1094) expressed a concern about certain a priori assumptions. Our methodology seems to imply that certain regularities in the phenomenon we were studying (the conscious experience of sleep onset) are universal. Group averaging and across-subject statistical reporting can cause researchers to overlook what he calls “idioversal regularities”. In effect, what might be critically important about the phenomenon is that it is so various; it is achievable in many ways. We (Lane and Yang 2010) agree that this may well be true of sleep onset. And, my provisional view is that it is even more likely to be true of mental ownership; we should anticipate the possibility that it might be variously achieved. Sensitivity to this concern, a concern about certain a priori assumptions, is yet another among the contributions that philosophy can make to cognitive neuroscience. It significantly influences the choice of methodology.

5. Conceptual Analysis: explicating “self”

Although “mental ownership” is not a term-of-art in the philosophy of mind, “self” is. Since “mental ownership” implies “self”, “self” is a term that must be explicated with great care. And since there is a long philosophical tradition of grappling with this difficult notion, it would be foolhardy to ignore the wealth of research that has already been conducted by philosophers.

Naturally though, time is a constraint. Since analysis of the concept of “self” is but one component in the development of this nascent theory and in the promotion of a research program, not all recent philosophical research in this area can be adequately addressed. Therefore, necessarily, during the second year of my project—when “self” will be the focus of philosophical analysis—I must be selective, selective in a way motivated partially by pragmatic concerns. Accordingly I will concentrate on those recent works that focus on “self” and that do so in such a way that they attempt, at least to a limited extent, to engage the empirical sciences. Strawson (2009) will be especially important in this regard since, although his work is motivated almost exclusively by familiar philosophical concerns, he (2009: xv) regards his treatise as “a work of psychology (the more

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philosophical division), and many of the claims in it are open to, and I believe deserve, empirical investigation.”

6. Normative Concerns: the fitting together of various levels

Science cannot always just proceed by asking “what is the case?” Often it must ask, “howshould one proceed?” One area of inquiry for which this normative concern is of special importance concerns the integration of distinct levels-of-description (e.g. the mental and neural). How should we regard the relationship between these two? This is a concern about which philosophers, especially philosophers of science, have, arguably, been more insightful than have most practicing scientists. Whether one should be an eliminativist, an ontic reductionist, a theory reductionist, or whether one should seek some form of interlevel integration is not an arbitrary choice. Each entails different ways of thinking about the phenomenon that one seeks to explain, and matters greatly in determining the likelihood of making progress.

Here I adopt an approach similar to that which Craver (2007) has referred to as the search for a “mosaic level integration.” He attends to mechanism, but not in the pursuit of reduction.He makes it clear that, at least upon his interpretation of the history of neuroscience, progress is most likely to be made when one allows that one should look both “downward” and “upward”. “Downward” at least to the extent that one is seeking lower-level mechanisms for a higher-level phenomenon. (Borrowing a phrase from Kitcher, he [Craver 2007: 259] makes it clear that ignoring the mental would yield nothing but “a world of gory details unfiltered by a higher-level perspective”.) “Upward,” in the sense that one seeks to identify the entities and activities, as well as the properties and their organization, in terms of which a mental phenomenon—like belongingness—is constituted. This up-down pincers maneuver, should strive for “mutual manipulability,” such that one should be able to manipulate the neural level by manipulating the mental level, and vice versa. Moreover, one should aim to show how lower-level events “are organized—spatially, temporally, and actively—with other components” such that the mental events might be realized.

When seeking inter-level integration, one must deal with multiple constraints. One such constraint, one that is of special importance here—since I am dealing with a phenomenon, mental ownership, that was not previously recognized—is the accommodation constraint (Craver 2007: 122-128 and 259-261). As studies carried out at the neural and mental levels co-evolve, some measure of mutual

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accommodation will likely be required. The history of neuroscience reveals that motivation for such accommodations can be top-down or bottom-up. One not uncommon consequence is that re-characterization of the explanandum is required. I anticipate that characterization of “belongingness” will require much further tinkering and refinement.

The goal of this research program is, in part, to discover the mechanism(s) of belongingness. To take this as a goal is, in Craver’s term (2007: 266), to provide a “scaffold” for constraints, fully aware that characterization of the phenomenon might evolve. Interlevel explanatory linkages are to be forged by identifying appropriate entities and activities, as well as their organization, and demonstrating their specific relevance to the explanandum—belongingness. Unlike reductionist approaches, here it is taken to be a methodological virtue that probes are made at different levels, because each level carries with it presuppositions that are independent of one another. When they converge in such a way as to shrink the space of plausible mechanisms, precisely because their presuppositions are distinct, our epistemic confidence can, justifiably, increase.

7. Belongingness as explanandum and as explanans:

Of course, a central motivation for this research is that belongingness is a phenomenon that needs to be explained. Accordingly, it is here treated as an explanandum. For too often, and for too long, it has simply been presupposed by scientists and treated through conceptual analysis by philosophers. But I (2009, 2010, and Forthcoming) have shown that such attitudes and approaches are inadequate.

It is in some respects analogous to causation, which tends to be presupposed by scientists, and treated only through conceptual analysis by philosophers. To extend the analogy from philosophical work on causation—which has famously been described as “the cement of the universe” (Mackie 1980)—one might say that investigations into mental ownership are investigations into the “cement” of the mind. I am trying to explain this cement.

But, as the ideas become more mature, especially when we are struck by a highly counter-intuitive phenomena—e.g. the fact that a simple rubber hand can be made to feel as though it is mine—accumulated findings concerning belongingness will be put to use as explanans, that is they will help to explain how belongingness obtains. Explanation often proceeds from “how possibly” questions (1965: 428-432): e.g. how possibly could a healthy person be made to feel that a

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rubber hand belongs to them, while their actual hand does not? As MOT becomes more sophisticated, it will help to explain “how actually” (Craver 2007: 112-113) belongingness is realized.

8. An evolving relationship between philosophy and science:

Patricia Churchland (2008: 409) has recently written that “the history of science can be seen as a gradual process whereby speculative philosophy cedes intellectual space to increasingly well-grounded experimental disciplines.” She goes on to proclaim that we are now living in an era during which classical philosophy of mind questions about self and consciousness, which once could only have been addressed through a priori conceptual analysis, are now being addressed by the empirical sciences. She adds that: (a) a priori, conceptual strategies “ran up against a torrent of neuropsychological results that clashed with the ‘truths’ of folk intuition”; (b) “because the data are the data, in place of these alleged ‘truths’ arose empirical questions about brain mechanisms”; and, (c) “the mind turns out to be rather different from how it appears”.

Although MOT was born of an attempt to challenge an alleged conceptual truth, IEM, discovered by a priori methods, and to challenge it by drawing upon the resources of empirical science, we must always be careful not to be excessively hasty or sweeping in our dismissal of classical approaches. The best practicing scientists are sensitive to fine conceptual distinctions, in ways that are evocative of sophisticated philosophical analysis. The data are never just the data; they themselves are the result of concatenations of interpretation, and they in turn lend themselves to re-interpretation when attempts are made to match them to theory. And, how things “appear” cannot be so easily dismissed from the study of mind as from the study of physics, at least because “appearances” are part of that which we seek to understand, part of the explanandum.

I believe that Shoemaker, Rosenthal and most other philosophers are wrong about immunity-to-error. But, even if I am correct, that is not the end of the story. It is, frankly, just the beginning. If we are not immune to error, if belongingness cannot be explained as a tautology, then how is it be explained? I believe this and related issues are just now becoming empirically tractable. Nevertheless, part of the aim of this research program and part of the goal of MOT is to seek refinement of relevant concepts, to give plausible interpretations of data relevance, and to explain the appearance. For all three of these purposes philosophical analysis is indispensable.

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9. Promotion of a research program, development of a theory:

To a first approximation, what I am trying to promote is an interdisciplinary research program. Lakatos’s (1970 and 1981) ideas partially reflect my views. Of course I do not envision my role as that of a historian of science, one who is trying to assess the status of research programs from the perspective of an outsider. Instead, I am trying to bootstrap a theory—MOT—into existence, by drawing upon the limited resources that are available to me—some the result of philosophical analysis, some that derive from new experimental paradigms, some that are to be found in pathological case studies. I liken this effort to Lakatos for several reasons, not the least of which is that it aspires to his sense of “progressive.”

On this view a theory may be said to be progressing when theoretical growth anticipates empirical growth—that is, if the theory predicts novel facts successfully, it is growing. A goal of MOT is to avoid seeking a level of comfort from which one gives only post hoc explanations of chance discoveries or discoveries produced by advocates of rival theories. If the research program is to grow, the theory must be revised in such a way that it need not depend upon post hoc explanations and that it predicts discoveries of rival theories, without sacrificing the core principles which enabled it to achieve its initial successes.

The mental ownership research program is guided by two leading ideas—the two negative theses and the two positive corollaries of MOT that are given below. These, at least for now, constitute the hard core—a set of commitments that cannot easily be abandoned. The seven conjectures, as they now stand, are treated as part of the protective belt. They are more open to change; if they cease to anticipate novel facts, they might need to be abandoned. Alternatively, their failure might imply that something is wrong with the hard core.

So, in a sense, it can be said that the hard core is not so hard. If a research program proceeds well—if it progresses—its motivating theories may well need to undergo change, changes that reflect development in various stages of the development of a central idea. Our understanding of belongingness may well need to change, just as ideas about atoms and gravity have changed, as the theories in which they were embedded were revised.

One reason for giving equal attention to conceptual analysis and empirical research is that the history of science teaches us that occasional anomalies or awkward empirical facts should not, necessarily prompt abandonment of theory.

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Many can perhaps be resolved by means of conceptual analysis—or at least formulated in such a way that they can be more effectively operationalized for use in experimental and clinical contexts. Only when theoretical growth begins to chronically fail to anticipate empirical growth, should the research program be deemed a failure. I believe that by developing MOT in the context of a research program, we are heeding Wackermann’s (2010) wise counsel and are creating the opportunity for scientific progress.

E. Results and Discussion, Part I: Self-Consciousness

i. Self-Consciousness and Immunity

One of the most seminal contributions to the understanding of self-consciousness over the last half century has been Sydney Shoemaker’s articulation of the idea that we are

“immune to error through misidentification relative to the first- person pronouns”

(IEM).1 Along with related ideas developed by Wittgenstein, Castenada, Evans, Perry,

and Pryor,2_{IEM has proven to be extremely fertile in stimulating insights into the} first-person perspective, “the distinctive way mental states present themselves to the

subjects whose states they are.”3 Moreover, Shoemaker’s formulation of the idea has

motivated significant interdisciplinary research into self-consciousness.4

Since first formulating his position, Shoemaker has done much to elaborate upon IEM and related notions. For more than four decades he has been perspicaciously developing his ideas on identification- freedom, introspection, self-knowledge, and the self-intimation of mental states. Although some aspects of Shoemaker’s views on immunity have been disputed, IEM itself has never been severely threatened by any empirical challenge.5

Perhaps the most substantial empirical challenge thus far attempted has been Campbell’s6 claim that schizophrenic thought insertions, understood in terms of the Frith7_{monitoring model, might serve as a counterexample to IEM. Gallagher and} Coliva have defended IEM by (among other things) arguing that since schizophrenic thoughts are still within a patient’s stream of consciousness, IEM is not vio- lated.8 They hold that, as a matter of conceptual truth, “if a subject is introspectively aware

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of a certain mental state, then she herself is having it and, therefore, that mental state is her own.”9

In this paper we argue that IEM fails. In section i, we adumbrate Shoemaker’s version of IEM along with related concepts central to his understanding of self-consciousness. We also reject the interpretation of IEM as a tautology, and propose to treat it as a hypothesis. In section ii, we present a clinical case—somatoparaphrenia—and in section iii we describe an experiment with healthy subjects—the Body Swap Illusion. In the former case, patients represent experienced sensations as belonging to someone other than self. In the latter, an illusion is created whereby subjects feel that they can shake hands with themselves. The one concerns bodily sensations; the other, the sense of agency.10_{Both cases reveal that} IEM lacks modal force: what IEM says cannot happen, can happen. In section iv we respond to possible criticisms of our position. In a concluding section we emphasize that in order to account for the phenomena which seem to defy IEM- based expectations, there is a need to distinguish the ownership of mental states from the ownership of body parts. Moreover, concerning the former, there is a compelling need to distinguish between mental states that are instantiated and mental states that are represented as belonging to oneself.

i. shoemaker’s immunity principle

In his reflections on self-consciousness, Shoemaker takes as a point of departure what he regards as an incontrovertible conceptual truth: “an experiencing is necessarily an experiencing by a subject of experience.”11 He evinces that a subject and an experience are just as inti- mately related as are a branch and a branch-bending. He then proceeds to develop a conception of self-consciousness that aspires to com- patibility with both naturalism and certain Cartesian intuitions.

Developing one among these intuitions, and taking his lead from Wittgenstein, Shoemaker marks a distinction between the use of “I” (and its cognates) “as subject” and its use “as object.”12 Use-as-subject refers to such expressions as “I am in pain”; use-as-object refers to such expressions as “I am bleeding.” Imagine, for example, that a base- runner and a catcher collide at home plate. As is not uncommon, the catcher’s leg is gashed by the spikes on the base-runner’s shoes, although the catcher does not immediately feel any pain. Because their limbs are entangled, upon first seeing the wound, the catcher does not immediately recognize it as his. As they disentangle, and as the catcher notices distinguishing features like the differences in their uniforms, he comes to realize that it is he who is bleeding. Recognition from the

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outside, so to speak, as in identifying the source of the bleeding, is recognition of self-as-object. The experience of pain, by contrast, given that it is known through introspection, typifies knowing about the self “as subject.”

Wittgenstein’s guiding intuition, one which is endorsed by Shoemaker, is: “...there is no question of recognizing a person when I say I have tooth-ache [sic]. To ask ‘are you sure it is you who have pains?’ would be nonsensical.”13 Shoemaker identifies the following as prototypical expressions of self-as-subject: “I feel pain”; “I

am waving my arm”; and “I see a canary.”14_{Clearly he believes that his argument is}

applica- ble to bodily sensation, to the sense of agency, and to perception of the external world. Take “I see a canary,” for example: I might be mistaken concerning what I actually see (it might be a cardinal). I might even

be hallucinating. But “it cannot happen that I am mistaken in saying this because I have misidentified as myself the person I know to see the canary.”15

Why should it be nonsensical to query whether one is certain that it is oneself who is experiencing the mental state? Because, Shoemaker maintains, when we make a judgment like “I feel pain,” we are aware that “one does, oneself, feel pain...one is, tautologically, aware, not simply that the attribute feel(s) pain is instantiated, but that it is instantiated in oneself.”16 Accordingly, it simply “cannot happen that I am mistaken in saying ‘I feel pain’ because, although I do know of someone that feels pain, I

am mistaken in thinking that person to be myself.”17_{The same is true for judgments}

about hand-waving or seeing canaries. Notice that these cases exude the modal force of “cannot.” According to Shoemaker this is what makes self-consciousness special.

Shoemaker further elucidates IEM. He says that to claim that a statement “a is F” might be erroneous through misidentification relative to the term “a” is to allow for the following possibility: “the speaker knows some particular thing to be F, but makes the mistake of asserting ‘a is F’ because, and only because, he mistakenly thinks that the thing he knows to be F is what ‘a’ refers to.”18 But for IEM statements, mistakes of this type are not possible. If the ground of my judgment is introspection,19 whenever I say “I feel pain” it cannot be the case that I am mistaken in thinking that the person in pain is me. Likewise, whenever I say “I am waving my arm” or “I see a canary” it cannot be the case that I have erroneously identified myself as the person who waves his arm or sees the canary.

How is it that immunity should obtain in such cases? Shoemaker replies that the relevant mental states are identification-free. He believes that even when we need to identify self (as-object), identification “will always presuppose the prior possession of

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other first-person information.”20 If self-consciousness always involved

identification, whenever

we self-ascribed a mental state (for example, “a is F ”) we would need to establish both “b is F ” and “a 5 b.” But “b is F,” in turn, would further require that “c is F ” and “b 5 c ” be established. To avoid an infinite regress, we must allow for first-person knowledge that is not grounded in an act of identification.

To illustrate this concern, consider the following. If I notice someone on a shopping center video display, I might wonder whether it is me. In order to make a proper identification, I might pull on my cap while checking to see whether the person on the video display does likewise. To perform this act of identification I must know that I myself am pulling on my cap. How can I know that? According to Shoemaker, my first- person knowledge that I am pulling on my cap must be grounded in identification-free first-person knowledge, because the only alternative would be just the sort of vicious infinite regress schematized above.21

Identification-freedom is also integrally related to his views on introspection, the self-intimating character of mental states, and the impos- sibility of self-blind creatures. For Shoemaker, introspective knowledge refers to just routine, mundane sorts of knowledge.22 In his reflections on how best to understand introspection, he rejects “inner sense” models, notably the “object perception model” (OPM) and the “broad percep- tual model” (BPM).

According to Shoemaker, if OPM is correct, then “identification information” about the perceived object must be available.23 Critically, these objects would need to be independent of acts of perception. But Shoemaker denies that there is any such role for awareness of self- as-object to play in the explanation of introspective knowledge. Although it might appear to be the case that self is a good candidate for being an object of perception, Shoemaker believes that when we do need to identify self-as-object, identification “will always presuppose the prior possession of other

first-person information.”24 Again, the only alternative to freedom from

identification would be profligate identification, identification that cannot but lead to vicious infinite regress.

Shoemaker also rejects BPM, which differs from OPM in concerning itself with facts rather than objects.25_{Despite this difference, though,}

BPM shares a fundamental commitment to the view that in perception we have access to things that are independent of being perceived. So identification-freedom would be incompatible with this model too.

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Shoemaker’s rejection of BPM is also linked to his rejection of the possibility of “introspective self-blindness.” He believes that a significant— and unacceptable—consequence of BPM is that it allows for the logical possibility of this particular kind of blindness.26 To be introspectively self- blind with respect to certain kinds of mental phenomena would require that, despite being able to conceive of those phenomena ( just as the blind can conceive of phenomena unseen), a creature would be unable to introspectively access them. According to Shoemaker, BPM is only worth taking seriously if self-blindness is regarded as a conceptual possibility.27 But he regards this notion to be as absurd as the claim that we could have pains but be systematically and blithely unaware of them.28

In short, in addition to IEM, Shoemaker endorses a “modest Carte- sianism,” a “weak version of the self-intimation thesis” (WST). On this view, the existence of certain mental entities is constitutively related to their being available to introspection. For those mental states that have phenomenal character, for example, it is of their essence that having them “issues in the subject’s being introspectively aware of that character, or does so if the subject reflects.”29 There might well be internal states to which we do not have introspective access, states that play an important role in causing behavior. But Shoemaker says such states would not count as mental. The proper way to think of the relationship between introspection and mental states is that “the reality known and the faculty for knowing it are...made for each other—neither could be what it is without the other.”30

Most philosophers regard IEM as a semantic or conceptual thesis. Recall that, according to Shoemaker, when one proclaims self to be in pain “one does, oneself, feel pain...one is, tautologically, aware, not simply that the attribute feel(s) pain is instantiated, but that it is instantiated in oneself.” Unlike Shoemaker, we do not regard this as a tautology. On the contrary, it can be subjected to empirical investigation. Our main thesis is: awareness that mental states are instantiated does not entail awareness that said states are instantiated in self. Unlike most critics of Shoemaker, for the sake of argument, we grant

that most of his views are correct. Even so, we argue that genuine counter-examples to IEM exist.

ii. iem and bodily sensations: somatoparaphrenia

Somatoparaphrenia is a syndrome that is characterized by the sense of profound estrangement from parts of one’s body.31 It is typically found in patients who have suffered extensive right-hemisphere lesions (usually vascular).32_{Lesions in the}

自我與現象意識

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