According to a common philosophical intuition, the deep nature of things is hidden from us, and the world as we know it through perception and science is, just like a dream, shadows, or a computer simulation, somehow shallow and lacking in reality. This “intuition of unreality” clashes with a strong, but perhaps more naive, intuition to the effect that the world as we know it seems perfectly real. Shadows, dreams, or informational structures appear too unreal to be identical to the (...) world as we know it! This clash between the two intuitions forms the basis of the “problem of reality.” In the late nineteenth century psychiatrists encountered patients they referred to as “metaphysician doubters” who constantly questioned the reality of the world. This essay draws on studies of these patients in order to reject, and indeed diagnose, the intuition of unreality and recent metaphysical doctrines drawing on it, such as structuralism, digitalism, and virtual realism. (shrink)

According to a common philosophical intuition, the deep nature of things is hidden from us, and the world as we know it through perception and science is somehow shallow and lacking in reality. For all we knwo, the intuition goes, we could be living in a cave facing shadows, in a dream or even in a computer simulation, This “intuition of unreality” clashes with a strong, but perhaps more naive, intuition to the effect that the world as we know it (...) seems perfectly real. Shadows, dreams, or informational structures appear too unreal to be identical to the world as we know it! This clash between the two intuitions forms the basis of the "problem of reality." At the turn of the nineteenth century psychiatrists encountered patients they referred to as “metaphysician doubters” who constantly questioned the reality of the world. This essay draws on the study of these patients to reject, and indeed diagnose, the intuition of unreality and recent metaphysical doctrines drawing on it, such as structuralism, digitalism, and virtual realism. (shrink)

Patients suffering from depersonalization complain of feeling detached from their body, their mental states, and actions or even from themselves. In this chapter, I argue that depersonalization consists in the lack of a phenomenal feature that marks my experiences as mine, which is usually called “mineness,” and that the study of depersonalization constitutes a neglected yet incomparable probe to assess empirically the scope, role, and even the nature of mineness. Here is how I will proceed. After describing depersonalization (§2) and (...) arguing that it involves a lack of mineness (§3) I will confront a series of objections (§4). I will then spell out what depersonalization can teach us about the scope of mineness (§5), about its role and psychological function (§6) and even about its nature (§7). (shrink)

If I see, hear, or touch a sparrow, the sparrow seems real to me. Unlike Bigfoot or Santa Claus, it seems to exist; I will therefore judge that it does indeed exist. The “sense of existence” refers to the kind of awareness that typically grounds such ordinary judgments of existence or “reality.” The sense of existence has been invoked by Humeans, Kantians, Ideologists, and the phenomenological tradition to make substantial philosophical claims. However, it is extremely controversial; its very existence has (...) been called into question. This paper aims to clarify the nature and reality of the sense of existence by studying a psychiatric condition in which the sense appears to be disrupted: depersonalization disorder (DPD). (shrink)

The goal of this article is to present a first list of ethical concerns that may arise from research and personal use of virtual reality (VR) and related technology, and to offer concrete recommendations for minimizing those risks. Many of the recommendations call for focused research initiatives. In the first part of the article, we discuss the relevant evidence from psychology that motivates our concerns. In Section “Plasticity in the Human Mind,” we cover some of the main results suggesting that (...) one’s environment can influence one’s psychological states, as well as recent work on inducing illusions of embodiment. Then, in Section “Illusions of Embodiment and Their Lasting Effect,” we go on to discuss recent evidence indicating that immersion in VR can have psychological effects that last after leaving the virtual environment. In the second part of the article, we turn to the risks and recommendations. We begin, in Section “The Research Ethics of VR,” with the research ethics of VR, covering six main topics: the limits of experimental environments, informed consent, clinical risks, dual-use, online research, and a general point about the limitations of a code of conduct for research. Then, in Section “Risks for Individuals and Society,” we turn to the risks of VR for the general public, covering four main topics: long-term immersion, neglect of the social and physical environment, risky content, and privacy. We offer concrete recommendations for each of these 10 topics, summarized in Table 1. (shrink)

This essay considers the role of depersonalization in the philosophy of Merleau-Ponty. While there has been a modest amount of interest in depersonalization from a phenomenological perspective, a critical exploration of the theme of depersonalization in Merleau-Ponty’s thinking itself remains overlooked ; Colombetti and Ratcliffe. This is an oddity, given that the theme of depersonalization proves instructive in Merleau-Ponty’s account of the constitution of the subject, and appears within Phenomenology of Perception at key points in his thinking. This paper serves (...) as a critical exposition of the role of depersonalization in Merleau-Ponty’s thought. I proceed in three ways. In the first instance, I provide an overview of depersonalization, addressing its salient characteristics, which includes: a feeling of disturbed bodily subjectivity; a diminishment of affective feeling; and a corresponding and overarching sense of unreality, carrying with it a sense of estrangement. In the main part of the paper, I consider the articulation of depersonalization in Merleau-Ponty, especially as it figures in Phenomenology of Perception. My claim is that depersonalization can be best captured as an expression of Merleau-Ponty’s idea of ambiguity. I conclude by considering to what extent Merleau-Ponty’s account of depersonalization corresponds with the medical understanding of the condition. (shrink)

Depersonalization is characterised by a profound disruption of self-awareness mainly characterised by feelings of disembodiment and subjective emotional numbing.It has been proposed that depersonalization is caused by a fronto-limbic suppressive mechanism – presumably mediated via attention – which manifests subjectively as emotional numbing, and disables the process by which perception and cognition normally become emotionally coloured, giving rise to a subjective feeling of ‘unreality’.Our functional neuroimaging and psychophysiological studies support the above model and indicate that, compared with normal and clinical (...) controls, DPD patients show increased prefrontal activation as well as reduced activation in insula/limbic-related areas to aversive, arousing emotional stimuli.Although a putative inhibitory mechanism on emotional processing might account for the emotional numbing and characteristic perceptual detachment, it is likely, as suggested by some studies, that parietal mechanisms underpin feelings of disembodiment and lack of agency feelings. (shrink)