On a common view of scenario-based sceptical arguments sceptical scenarios are error-possibilities, i.e. their point is to introduce the possibility of having only false beliefs. However, global error is impossible for purely logical/conceptual reasons: Even if one’s beliefs are consistent, the negations of one’s beliefs need not be consistent as well. My paper deals with the question of what the consequences of this result are. Two attempts at repairing scenario-based sceptical arguments within the framework of understanding sceptical scenarios as error-possibilities (...) are found wanting. Instead, what should be given up is the assumption that sceptical scenarios are error-possibilities. What is thought-provoking about the scenario of the brain in a vat is not that none of its empirical beliefs are true, but that all of its empirical beliefs fall short of knowledge at the same time. Hence, sceptical scenarios are not error-possibilities, but ignorance possibilities. If this is so, both the closure argument and the underdetermination argument commit a subtle mistake and should be replaced by slightly different arguments. The principle of excluded ignorance-possibilities turns out to be an epistemological principle that is faithful to scepticism’s tenets without misinterpreting sceptical scenarios as error-possibilities. (shrink)

A growing number of researchers in the business ethics field have used scenarios as a data gathering technique in their empirical investigations of ethical issues. This paper offers a review and critique of 26 studies that have utilized scenarios to elicit inferences of ethical reasoning, decision making, and/or intended behavior from managerial or student populations. The use of a theoretical foundation, the development of hypotheses, various characteristics germane to the use of scenarios, population and sampling issues, and the use of (...) statistical measures are explored and assessed. In the interest of improving scenario-based research, ten recommendations are presented to guide future scenario research. (shrink)

In order to solve problems, humans are able to synthesize apparently unrelated concepts, take advantage of serendipitous opportunities, hypothesize, invent, and engage in other similarly abstract and creative activities, primarily through the use of their visual systems. In _Scenario Visualization_, Robert Arp offers an evolutionary account of the unique human ability to solve nonroutine vision-related problems. He argues that by the close of the Pleistocene epoch, humans evolved a conscious creative problem-solving capacity, which he terms scenario visualization, that enabled them (...) to outlive other hominid species and populate the planet. Arp shows that the evidence for scenario visualization -- by which images are selected, integrated, and then transformed and projected into visual scenarios -- can be found in the kinds of complex tools our hominid ancestors invented in order to survive in the ever-changing environments of the Pleistocene world. Arp also argues that this conscious capacity shares an analogous affinity with neurobiological processes of selectivity and integration in the visual system, and that similar processes can be found in the activities of organisms in general. The evolution of these processes, he writes, helps account for the modern-day conscious ability of humans to use visual information to solve nonroutine problems creatively in their environments. Arp's account of scenario visualization and its emergence in evolutionary history suggests an answer to two basic questions asked by philosophers and biologists concerning human nature: why we are unique; and how we got that way. Robert Arp is Postdoctoral Research Fellow at the National Center for Biomedical Ontology. His areas of specialization include philosophy of biology and philosophy of mind. He is the author of numerous articles and the forthcoming An Integrated Approach to the Philosophy of Mind. (shrink)

In this paper, I first present the ideas and arguments put forward by evolutionary psychologists that humans evolved certain capacities to creatively problem solve. Specifically, Steven Mithen thinks that creative problem solving is possible because the mind has evolved a conscious capacity he calls cognitive fluidity, the flexible exchange of information between and among mental modules. While I agree with Mithen that cognitive fluidity acts as a necessary condition for creative problem solving, I disagree that cognitive fluidity alone will suffice (...) for such an activity. I argue further that the flexible exchange of information between and among modules, as well as what I call scenario visualization - a conscious ability to segregate and integrate visual images in future scenarios - evolved in our species and accounts for certain kinds of creative problem solving. (shrink)

This article presents a novel set of ten play scenarios for robot-assisted play for children with special needs. This set of scenarios is one of the key outcomes of the IROMEC project that investigated how robotic toys can become social mediators, encouraging children with special needs to discover a range of play styles, from solitary to collaborative play. The target user groups in the project were children with Mild Mental Retardation,1 children with Severe Motor Impairment and children with Autism. The (...) play scenarios were developed against specific educational and therapeutic objectives that were discussed with panels of experts in various countries, during several user panel meetings for each of the above mentioned target user groups. These objectives were classified with reference to the ICF-CY, the International Classification of Functioning – version for Children and Youth. The article presents a detailed description of the play scenarios, each with its relevant educational and therapeutic objectives in five key developmental areas. While the play scenarios described in this paper originally were developed for and tested with the above user groups and with the IROMEC robot, the play scenarios can potentially be applied to other user groups and to a wide range of other applications involving human-robot interaction using different robotic toys. Keywords: human-robot interaction; assistive technology; play scenarios; autism; mild mental retardation; sever motor impairment; assisted play. (shrink)

Some Scenarios for What is Coming Down on Us .

Van Koppen and Mackor offer a scenario‐approach analysis of the case. They first explicate their approach, linking it to inference to the best explanation and theories of explanatory coherence. An important distinction in their analysis is between explaining known facts and predicting novel facts. They claim that their approach is cognitively feasible and stays close to descriptive theories of evidential reasoning. They want to keep it informal, so that legal professionals can apply it.

This article investigates structural aspects of source domains in metaphorical mappings with regard to their manifestation in public discourse data. Specifically, it analyses the organization of source concepts into mininarratives or "scenarios" that dominate the discourse manifestations of source domains. The material consists of examples from a bilingual corpus of British and German public debates about the &European Union.& The data show that while the two national samples share some basic mappings between the source and target domains, they each are (...) characterised further by specific scenarios that provide focal points for conceptualizing the target topic. The scenarios can also be shown to carry evaluative and attitudinal biases that are related to particular political dispositions and preferences of the respective national discourse communities. In conclusion, it will be argued that the analysis of scenarios is a necessary complement to the study of source domains and of domain-mappings in metaphorical language use. (shrink)

Promoting respect for the four principles remains of great practical importance in ordinary medicineThe following are four “scenarios” with brief outlines of how Raanan Gillon has analysed them using the “four principles” approach. These are the four cases that the commentators were asked to analyse.Professor Gillon has for many years advocated the use of the Beauchamp and Childress four principles approach as a widely and interculturally acceptable method for medical ethics analysis . At present there seems to be a backlash (...) by some bioethicists against this approach, with among others, adherents of feminist ethics, narrative ethics, virtue ethics, and various varieties of regional ethics claiming to offer better approaches to medical ethics.At Raanan Gillon’s request this special issue of the Journal of Medical Ethics is intended to focus on this aspect of his work, with a view not only to discussing the issue of how different approaches to medical ethics are and/or are not compatible with the four principles approach but also to make clear to JME readers what alternative ethics analysis method is preferred and used by the various commentators.THE “STANDARD” JEHOVAH’S WITNESS CASEIn the first scenario, that of the “standard” Jehovah’s Witness case, a competent adult patient loses a massive amount of blood from a blood vessel bleeding in an acute duodenal ulcer. The best chance of …. (shrink)

Natural scientists have proposed that humankind has entered a new geologic epoch. Termed the “Anthropocene,” this new reality revolves around the central role of human activity in multiple Earth ecosystems. That challenge requires a rethinking of social science explanations of organization and environment relationships. In this article, we discuss the need to politicize institutional theory as a means understanding “Anthropocene Society,” and in turn what that resultant society means for the Anthropocene in the natural environment. We modify the constitutive elements (...) of institutional orders and a set of main change mechanisms to explore three scenarios around which future Anthropocene Societies might be built—Collapsing Systems, Market Rules, and Cultural Re-Enlightenment. Simultaneously, we use observations from the Anthropocene to expose limitations in present institutional theory and propose extensions to remedy them. Overall, this article challenges organizational scholars to consider a new paradigm under which research in environmental sustainability and social sustainability takes place. (shrink)

Climatologists have recently introduced a distinction between projections as scenario-based model results on the one hand and predictions on the other hand. The interpretation and usage of both terms is, however, not univocal. It is stated that the ambiguities of the interpretations may cause problems in the communication of climate science within the scientific community and to the public realm. This paper suggests an account of scenarios as props in games of make-belive. With this account, we explain the difference between (...) projections that should be make-believed and other model results that should be believed. (shrink)

Background This study used a scenario- and discussion-based approach to teach preclinical medical students the socio-philosophical aspects of psychiatry and qualitatively evaluated the learning outcomes in a medical humanities course in Taiwan. Methods The seminar session focused on three hypothetical psychiatry cases. Students discussed the cases in groups and were guided by facilitators from multiple disciplines and professions. At the end of the semester, students submitted a narrative report comprising their reflections on the cases and discussions. The authors utilized content (...) analysis to categorize students’ narratives into three facets, namely, the philosophical, social and individual. Results In total 163 preclinical medical students participated in the class; 150 of them mentioned the scenario-based lesson in their reports; 33.3% of these reports discussed the case at the philosophical dimension (n = 50), 45.3% at the social dimension (n = 68), and 26.6% at the individual dimension (n = 40). Four major themes emerged: (1) a psychiatric diagnosis has far-reaching consequences for an individual’s life, (2) the social structure affects how patients experience psychiatric disorders, (3) students related personal experience or those of friends and family to understand psychiatric disorders, and (4) medical humanities are of particular importance in psychiatric education. Conclusions This study demonstrated that the scenario-based discussions led by a multidisciplinary team of facilitators can benefit medical students with limited clinical experience to contemplate the socio-philosophical aspects of psychiatry. The authors suggest that this pedagogical model during preclinical education should be encouraged. (shrink)

Qu’en est-il de la transmission généalogique de la honte? Après avoir rappelé la différence entre avoir, être et porter la Honte, l’auteur présente la notion de scénario généalogique porte-la-Honte en particulier à propos de la conception d’un enfant. Il décrit, en l’illustrant à partir d’un exemple de thérapie familiale psychanalytique et de traumatisme catastrophique communautaire, l’importance de la figuration narrative dans la clinique de la honte dans une perspective psychanalytique des liens.

Qu’en est-il de la transmission généalogique de la honte? Après avoir rappelé la différence entre avoir, être et porter la Honte, l’auteur présente la notion de scénario généalogique porte-la-Honte en particulier à propos de la conception d’un enfant. Il décrit, en l’illustrant à partir d’un exemple de thérapie familiale psychanalytique et de traumatisme catastrophique communautaire, l’importance de la figuration narrative dans la clinique de la honte dans une perspective psychanalytique des liens.

The EU Artificial Intelligence Act (AIA) defines four risk categories for AI systems: unacceptable, high, limited, and minimal. However, it lacks a clear methodology for the assessment of these risks in concrete situations. Risks are broadly categorized based on the application areas of AI systems and ambiguous risk factors. This paper suggests a methodology for assessing AI risk magnitudes, focusing on the construction of real-world risk scenarios. To this scope, we propose to integrate the AIA with a framework developed by (...) the Intergovernmental Panel on Climate Change (IPCC) reports and related literature. This approach enables a nuanced analysis of AI risk by exploring the interplay between (a) risk determinants, (b) individual drivers of determinants, and (c) multiple risk types. We further refine the proposed methodology by applying a proportionality test to balance the competing values involved in AI risk assessment. Finally, we present three uses of this approach under the AIA: to implement the Regulation, to assess the significance of risks, and to develop internal risk management systems for AI deployers. (shrink)

Avoiding whinges from various and potentially conflicting stakeholders is a major challenge for sustainable development and for the identification of sustainability scenarios or policies for biodiversity and ecosystem services. It turns out that independently complying with whinge thresholds and constraints of these stakeholders is not sufficient because dynamic ecological-economic interactions and uncertainties occur. Thus more demanding no whinge standards are needed. In this paper, we first argue that these new boundaries can be endogenously exhibited with the mathematical concepts of viability (...) kernel and viable controls. Second, it is shown how these no whinge kernels have components, such as harvesting of resources, that should remain within safe corridor while some other components, in particular biodiversity, have only lower conservation limits. Thus, using radar charts, we show how this no whinge kernels can take the shape of a tree that we name viability tree. These trees of viability capture the idea that the unbounded renewal potential of biodiversity combined with a bounded use of the different ecosystem services are crucial ingredients for the sustainability of socio-ecosystems and the design of no whinge policies reconciling the different stakeholders involved. (shrink)

The osmotic activity produced by internal, non‐permeable, anionic nucleic acids and metabolites causes a persistent and life‐threatening cell swelling, or cellular edema, produced by the Gibbs‐Donnan effect. This evolutionary‐critical osmotic challenge must have been resolved by LUCA or its ancestors, but we lack a cell‐physiology look into the biophysical constraints to the solutions. Like mycoplasma, early cells conceivably preserved their volume with Cl−, Na+, and K+‐channels, Na+/H+‐exchangers, and a light‐dependent bacteriorhodopsin‐like H+‐pump. Here, I simulated protocells having these ionic‐permeabilities and inhabiting (...) an oceanic pond before the Great‐Oxygenation‐Event. Protocells showed better volume control and stable resting potentials at lower external pH and higher temperatures, favoring a certain type of extremophile life. Prevention of Na+‐influx at night, with low bacteriorhodopsin activity, required deep shutdown of highly voltage‐sensitive Na+‐channels and extremely selective K+‐channels, two conserved features essential for modern neuronal encoding. The Gibbs‐Donnan effect universality implies that extraterrestrial cells, if they exist, may reveal similar volume‐controlling mechanisms. (shrink)

"The importance of questions is beyond doubt. But the degree of attention paid to them in logic and linguistics is still less than they deserve." What is a question? How to represent questions in formal languages? How to model reasoning in which questions are involved? Can we prove anything by means of pure questioning? How to model goal-directed problem solving? These are the main issues of Andrzej Wi niewski's "Questions, Inferences, and Scenarios." This book offers a state-of-the-art exposition of Inferential (...) Erotetic Logic, that is, an approach to the logic of questions focused on inferences which lead to questions as conclusions. Wi niewski characterizes semantic relations which determine validity of these inferences within the framework of Minimal Erotetic Semantics, applicable to a wide range of formal languages. He elaborates in detail the concept of erotetic search scenario, a tool for modelling problem solving. Moreover, the author presents some applications of Inferential Erotetic Logic in proof theory. Andrzej Wi niewski is one of the most prominent contemporary researchers in the logic of questions. Currently, he is a full professor at the Department of Logic and Cognitive Science, Institute of Psychology, Adam Mickiewicz University in Pozna, Poland. (shrink)

On peut distinguer trois cas de correspondances différentes entre les « scénarios schématiques » et le domaine narratif folklorico-littéraire : 1. La narration constitue la projection de la « dramaturgie de la vie » (une telle projection n’est évidemment ni directe ni complète) ;2. La structure de l’univers des personnages et la structure événementielle du narratif influencent la formation des « scénarios de la vie », en conditionnant l’apparence morphologico-compositionnelle de l’un et de l’autre ;3. La coincidence de (...) la « dramaturgie de la vie » et de la « dramaturgie de la narration»s’explique par le fait qu’elles ont des sources communes ; ces sources pourraient être les modèles mentaux de la tradition, qui dictent à un homme des « règles de comportement » d’une part, et qui s’incarnent dans la narration folklorico-littéraire d’autre part. Le « scénario schématique » possède une structure événementielle, situationnelle et actantielle. À cette structure correspond un certain niveau d’interprétation qui souvent la lie directement à la conscience religieuse et mythologique ; une telle conscience — compte tenu du fait qu’une conceptualisation globale de tous les aspects de la vie humaine caractérise le mythe — englobe, par sa nature même, les « blocs interprétatifs » pertinents pour pratiquement tous les précédents événementiels. Le « scénario schématique » est donc lié au domaine des croyances et concepts actuels, lié aussi aux systèmes de valeurs et normes éthiques, etc. ; il est possible de reconstituer nombre de ces croyances, concepts, valeurs et normes à l’aide de l’histoire vécue qui nous occupe. D’ordinaire, ces interprétations ne représentent pas le fond neutre des événements, mais un élément actif et dynamique qui agit directement sur le développement de ces événements. (shrink)

Energy production and consumption give rise to issues of justice for future humans. By analysing a specific case – Swedish energy politics – this article contributes to the discussion of how consideration for future humans should affect energy policy making. It outlines three different energy scenarios for the period 2035-2065 – the nuclear-renewables, the renewables-low and the renewables-high scenarios – and assesses them from the point of view of justice for future individuals by using the capabilities approach as a normative (...) framework. We cannot make a definitive assessment of the different scenarios due to the great uncertainties involved in determining the impacts on individuals living between 2035 and 2065 and individuals born thereafter, but we still conclude that we have certain reasons to prefer the renewables-low scenario since it avoids certain risks connected with the other scenarios. The economic growth in this scenario is lower than in the others, but we question whether this is a disadvantage from the point of view of the capabilities approach. _Keywords:_ energy scenarios, justice, future generations, capabilities approach. (shrink)

This article will argue that there is a science of scenario planning; or at least a logos, a logic, a scenariology. Scenario planning is not predictive. But a good set of scenarios, scientifically developed, can reliably and predictably change minds. Scenario planning is both art and science. In joining the club of the sciences, scenario planning calls for a new kind of membership, or a new kind of science, one that, following Stuart Kauffman, relies on the importance of story. Hegel (...) tells us that all stories, all narratives include a conflict between desire and the law, intention, and necessity. Scenarios provide a way for communities to frame their intentions. They thereby effect "downward causality" on the present in order to project the present toward a preferred future. In fulfilling the promise of this new kind of science, scenario planning breaks with positivistic science, but without falling into a postmodern nihilism. Without setting out to do so, the discipline of scenario planning introduces us to a new epistemology, a new way of knowing the truth. Drawing on pragmatism, Wittgenstein, and Richard Rorty, this article reaches the conclusion that, for scenario planners, the future replaces objectivity as the horizon for justification. What is true? We'll see. (shrink)

Actualists hold that contrary-to-duty scenarios give rise to deontic dilemmas and provide counterexamples to the transmission principle, according to which we ought to take the necessary means to actions we ought to perform. In an earlier article, I have argued, contrary to actualism, that the notion of ‘ought’ that figures in conclusions of practical deliberation does not allow for deontic dilemmas and validates the transmission principle. Here I defend these claims, together with my possibilist account of contrary-to-duty scenarios, against Stephen (...) White’s recent criticism. (shrink)

Our aim is to model the behaviour of a cognitive agent trying to solve a complex problem by dividing it into sub-problems, but failing to solve some of these sub-problems. We use the powerful framework of erotetic search scenarios combined with Kleene’s strong three-valued logic. ESS, defined on the grounds of Inferential Erotetic Logic, has appeared to be a useful logical tool for modelling cognitive goal-directed processes. Using the logical tools of ESS and the three-valued logic, we will show how (...) an agent could solve the initial problem despite the fact that the sub-problems remain unsolved. Thus our model not only indicates missing information but also specifies the contexts in which the problem-solving process may end in success despite the lack of information. We will also show that this model of problem solving may find use in an analysis of natural language dialogues. (shrink)

Scenarios are flexible means to integrate disparate ideas, thoughts and feelings into holistic images, providing the context and meaning of possible futures. The application of narrative scenarios in engineering, development of socio-technical systems or communities provides an important link between general ideas and specification of technical system requirements. They focus on how people use systems through context-related storytelling rather than abstract descriptions of requirements. The quality of scenarios depends on relevant assumptions and authentic scenario stories. In this article, we will (...) explore how the narrative approach may enrich the scenario ‘skeleton’ with ‘flesh and blood’, that is, living, detailed and consistent storytelling. In addition, criteria are suggested for evaluation of the quality of scenario storytelling. (shrink)

Présente le parcours philosophique de Merleau-Ponty tant dans sa formation que dans ses objectifs. Ses références : Descartes, Leibniz, Gabriel Marcel. Ses concepts opératoires : le concret, l'incarnation, l'intentionnalité, les chiasmes.

An Authoritarian Scenario. The long-term war against « terrorism » embarked upon by the Bush administration in the aftermath of September 11th 2001 goes far beyond its strictly military dimension. It also involves a fundamental onslaught on democratic and social rights, both in the USA and in European countries. The result of this combination between the military and a political dimension is the establishment of an architecture of control operating in the service of the most brutal sectors of the imperialist (...) bourgeoisie and of the accumulation of capital. (shrink)

Concept politique à large spectre central à la philosophie contemporaine, la reconnaissance est une émotion morale dont l’histoire culturelle reste à tracer. Peut-être plus encore que d’autres affects, elle se place à l’articulation de questions psychologiques, anthropologiques et esthétiques, comme l’a montré l’histoire faite de Stephen Cave du concept de recognition. Ses mutations historico-esthétiques disent nos modes de redécouverte de l’autre, de la question de la cicatrice d’Homère à celle des retours des survivants de la Shoah, de l’anagnorisis grecque jusqu’au (...) romans de la reconnaissance impossible ( Le Colonel Chabert de Balzac) en passant par les problèmes posés aux dramaturges classiques par son usage. C’est sur ce chassé-croisé entre représentation et configuration performative par l’art de la reconnaissance que je voudrais me pencher. (shrink)

This article explores the process of “re-imagined scenarios,” through which the moments of contact with the 9/11 hijackers were developed into scenarios that came to play a central role in U.S. counterterrorism training and policy. Drawing on fieldwork and interviews with trainers, government officials, and police officers, it is argued that these scenarios do not recreate previous encounters, or conjure up possible futures, but instead rely on “the elasticity of the almost” to reactivate the past. The re-imagined scenarios call forth (...) "a certain array of recognizable elastic points," through which options for alternative movements are invented. (shrink)

This text studies the scenarios in which violence appears in ancient Greece, to demonstrate that the purpose of the visibility of violence in the tragic drama, as Jacqueline de Romilly says, is to give a lesson to men through extraordinary stories, that occur in a symbolic world, that speaks to the "generations of men", as we are told in Oedipus Rex , and a destiny where exemplary human condition is reported. The analysis of violence in ancient Greece done in this (...) paper, allows a contrast with the way violence is represented in the contemporary world. The author states that the “unmediated” visibility of violence produces a fracture in the intersubjective link, that is, a fracture in the symbolic link of political articulation. (shrink)

In philosophical logic and metaphysics there is a long-standing debate around the most appropriate structures to represent indeterministic scenarios concerning the future. We reconstruct here such a debate in a computational setting, focusing on the fundamental difference between moment-based and history-based structures. Our presentation is centered around two versions of an indeterministic scenario in which a programmer wants a machine to perform a given task at some point after a specified time. One of the two versions includes an assumption about (...) the future behaviour of the machine that cannot be encoded in any programming instruction; such version has models over history-based structures but no model over a moment-based structure. Therefore, our work adds a new stance to the debate: moment-based structures can be said to rule out certain indeterministic scenarios that are computationally unfeasible. (shrink)

Case-based instruction has been regarded by many as a viable alternative to traditional lecture-based education and training. However, little is known about how case-based training techniques impact training effectiveness. This study examined the effects of two such techniques: (a) presentation of alternative outcome scenarios to a case, and (b) conducting a structured outcome evaluation. Consistent with the hypotheses, results indicate that presentation of alternative outcome scenarios reduced knowledge acquisition, reduced sensemaking and ethical decision-making strategy use, and reduced decision ethicality. Conducting (...) a structured outcome evaluation had no impact on these outcomes. Results indicate that those who use case-based instruction should take care to use clear, less complex cases with only a singular outcome if they are seeking these types of outcomes. (shrink)

By their nature, the most vexing social problems reflect collisions between social and economic interests of parties with highly divergent views and perspectives on the cause and character of what is at issue and the consequences that flow from it. Conflicts around biotechnology applications are good examples of these problems. When considering the potential consequences of proposed biotechnology applications, an enormous range of perspectives arise reflecting the breadth of different and often competing interests with a stake in life's future.This essay (...) starts from an assumption that the traditional tool of cost‐benefit analysis is not adequate for adjudicating competing claims around the introduction of new biotechnology applications. It tends to require implicit simplifying assumptions that reduce or mask true underlying levels of complexity and uncertainty, and the results it produces deliver a definitive and singular answer, as opposed to a multiplicity of outcomes. In this essay, I describe some of the key elements of formal scenario planning to show how CBA could be redeployed as a supporting tool within the broader decision support methodology of formal scenario planning. (shrink)

A mathematical model of the natural origin of our universe is presented. The model is based only on well-established physics. No claim is made that this model uniquely represents exactly how the universe came about. But the viability of a single model serves to refute any assertions that the universe cannot have come about by natural means.

The aim of this paper is two-fold: first, it is intended to articulate theses that are often assessed independently, thus showing that a strong version of epistemological disjunctivism about perceptual knowledge implies a transformative conception of rationality. This entails that individuals in skeptical scenarios could not entertain rational thoughts about their environment, for they would fail to have perceptual states. The secondary aim is to show that this consequence is not a sufficient reason to abandon the variety of disjunctivism presented. (...) The argument for this claim depends on the assessment of rationality attributions to subjects in plausible cases of illusion and some clinical cases of hallucination. RESUMO Este artigo tem dois objetivos: primeiramente, pretende-se articular teses que são frequentemente avaliadas independentemente, mostrando com isso que uma versão robusta do disjuntivismo epistemológico sobre conhecimento perceptual implica uma concepção transformativa da racionalidade. Uma consequência disso é que indivíduos em cenários céticos não poderiam entreter pensamentos racionais sobre o ambiente em que habitam, pois eles não possuiriam estados perceptuais. Em segundo lugar, argumenta-se que a consequência delineada acima não é uma razão suficiente para rejeitar o disjuntivismo tal como apresentado. Esse argumento depende da avaliação de atribuições de racionalidade a indivíduos em casos plausíveis de ilusão e em alguns casos clínicos de alucinação. (shrink)