Luitzen Egburtus Jan Brouwer founded a school of thought whose aim was to include mathematics within the framework of intuitionistic philosophy; mathematics was to be regarded as an essentially free development of the human mind. What emerged diverged considerably at some points from tradition, but intuitionism has survived well the struggle between contending schools in the foundations of mathematics and exact philosophy. Originally published in 1981, this monograph contains a series of lectures dealing with most of the fundamental topics (...) such as choice sequences, the continuum, the fan theorem, order and well-order. Brouwer's own powerful style is evident throughout the work. (shrink)

For centuries, inconsistencies were seen as a hindrance to good reasoning, and their role in the sciences was ignored. In recent years, however, logicians as well as philosophers and historians have showed a growing interest in the matter. Central to this change were the advent of paraconsistent logics, the shift in attention from finished theories to construction processes, and the recognition that most scientific theories were at some point either internally inconsistent or incompatible with other accepted findings. The new interest (...) gave rise to important questions. How is `logical anarchy' avoided? Is it ever rational to accept an inconsistent theory? In what sense, if any, can inconsistent theories be considered as true? The present collection of papers is the first to deal with this kind of questions. It contains case studies as well as philosophical analyses, and presents an excellent overview of the different approaches in the domain. (shrink)

While numerous studies show that brain signals contain information about an individual’s current state that are potentially valuable for smoothing man-machine interfaces, this has not yet lead to the use of brain computer interfaces (BCI) in daily life. One of the main challenges is the common requirement of personal data that is correctly labelled concerning the state of interest in order to train a model, where this trained model is not guaranteed to generalize across time and context. Another challenge is (...) the requirement to wear electrodes on the head. We here propose a BCI that can tackle these issues and may be a promising case for BCI research and application in everyday life. The BCI uses EEG signals to predict head rotation in order to improve images presented in a Virtual Reality (VR) headset. When presenting a 360° video to a headset, Field-of-View approaches only stream the content that is in the current field of view and leave out the rest. When the user rotates the head, other content parts need to be made available soon enough to go unnoticed by the user which is problematic given the available bandwidth. By predicting head rotation, the content parts adjacent to the currently viewed part could be retrieved in time for display when the rotation actually takes place. Eleven participants generated left- and rightward head rotations while head movements were recorded using the headsets motion sensing system and EEG sensors. We trained neural network models to distinguish EEG epochs preceding rightward, leftward and no rotation. Applying these models to streaming EEG data that was withheld from the training showed that 400 ms before rotation onset, the probability ‘no rotation’ started to decrease and the probabilities of an upcoming right- or leftward rotation started to diverge in the correct direction. In the proposed BCI scenario, users already wear a device on their head allowing for integrated sensors. Moreover, it is possible to acquire accurately labeled training data on the fly, and continuously monitor and improve the model’s performance. The BCI can be harnessed if it will improve imagery and therewith enhance immersive experience. (shrink)

Expectation-based theories of language comprehension, in particular Surprisal Theory, go a long way in accounting for the behavioral correlates of word-by-word processing difficulty, such as reading times. An open question, however, is in which component of the Event-Related brain Potential signal Surprisal is reflected, and how these electrophysiological correlates relate to behavioral processing indices. Here, we address this question by instantiating an explicit neurocomputational model of incremental, word-by-word language comprehension that produces estimates of the N400 and the P600—the two most (...) salient ERP components for language processing—as well as estimates of “comprehension-centric” Surprisal for each word in a sentence. We derive model predictions for a recent experimental design that directly investigates “world-knowledge”-induced Surprisal. By relating these predictions to both empirical electrophysiological and behavioral results, we establish a close link between Surprisal, as indexed by reading times, and the P600 component of the ERP signal. The resultant model thus offers an integrated neurobehavioral account of processing difficulty in language comprehension. (shrink)

Ten years ago, researchers using event-related brain potentials to study language comprehension were puzzled by what looked like a Semantic Illusion: Semantically anomalous, but structurally well-formed sentences did not affect the N400 component—traditionally taken to reflect semantic integration—but instead produced a P600 effect, which is generally linked to syntactic processing. This finding led to a considerable amount of debate, and a number of complex processing models have been proposed as an explanation. What these models have in common is that they (...) postulate two or more separate processing streams, in order to reconcile the Semantic Illusion and other semantically induced P600 effects with the traditional interpretations of the N400 and the P600. Recently, however, these multi-stream models have been called into question, and a simpler single-stream model has been proposed. According to this alternative model, the N400 component reflects the retrieval of word meaning from semantic memory, and the P600 component indexes the integration of this meaning into the unfolding utterance interpretation. In the present paper, we provide support for this “Retrieval–Integration ” account by instantiating it as a neurocomputational model. This neurocomputational model is the first to successfully simulate the N400 and P600 amplitude in language comprehension, and simulations with this model provide a proof of concept of the single-stream RI account of semantically induced patterns of N400 and P600 modulations. (shrink)

Though the social world is real and objective, the way that social facts arise out of other facts is in an important way shaped by human thought, talk and behaviour. Building on recent work in social ontology, I describe a mechanism whereby this distinctive malleability of social facts, combined with the possibility of basic human error, makes it possible for a consistent physical reality to ground an inconsistent social reality. I explore various ways of resisting the prima facie case for (...) social inconsistency. I conclude, however, that the prima facie case survives scrutiny, and draw out some of the ramifications. (shrink)

This paper questions the shifting meaning of the ethical categories of proximity and alterity in the light of the technological and social changes that virtual social worlds went through. It takes Roger Silverstone’s key theme of “proper distance” as a point of departure, and discusses the significance of this concept by linking it up with the more media-theoretical approaches on virtual communication as developed in McLuhan’s and Baudrillard’s body of thought. It is argued that today’s virtual realities ask for both (...) a philosophical and media-sociological reconsideration of the traditional ethical category of alterity. As such, it links up with Feenberg’s idea that “online groups are indeed a qualitatively new medium” (A. Feenberg and M. Bakardjieva, “Virtual Community: No ‘Killer Implication,’” New Media & Society 6(1) (2004): 37–43, 41), but at the same time challenges Feenberg’s reservations about a theory of media centrism. (shrink)

The theory of collective agency and intentionality is a flourishing field of research, and our understanding of these phenomena has arguably increased greatly in recent years. Extant theories, however, are still ill-equipped to explain certain aspects of collective intentionality. In this article we draw attention to two such underappreciated aspects: the failure of the intentional states of collectives to supervene on the intentional states of their members, and the role of non-human factors in collective agency and intentionality. We propose a (...) theory of collective intentionality which builds on the ‘interpretationist’ tradition in metasemantics and the philosophy of mind as initiated by David Lewis and recently developed further by Robbie Williams. The collective-level analogue of interpretationism turns out to look different in some ways from the individual-level theory, but is well-suited to accommodating phenomena such as hybrid collective intentionality. Complemented with Kit Fine’s theory of variable embodiment, such a theory also provides a diachronic account of intentional collectives. (shrink)

Many philosophers believe that luck egalitarianism captures “desert-like” intuitions about justice. Some even think that luck egalitariansm distributes goods in accordance with desert. In this paper, we argue that this is wrong. Desertism conflicts with luck egalitarianism in three important contexts, and, in these contexts, desertism renders the proper moral judgment. First, compared to desertism, luck egalitarianism is sometimes too stingy: it fails to justly compensate people for their socially valuable contributions—when those contributions arose from “option luck”. Second, luck egalitarianism (...) is sometimes too restrictive: it fails to justly compensate people who make a social contribution when that contribution arose from “brute luck”. Third, luck egalitarianism is too limited in scope: it cannot diagnose economic injustice arising independently of comparative levels of justice. The lesson of this paper is that luck egalitarians should consider supplementing their theory with desert considerations. Or, even better, consider desertism as a superior alternative to their theory. (shrink)

As euthanasia has become a widely debated issue in many Western countries, hospitals and nursing homes especially are increasingly being confronted with this ethically sensitive societal issue. The focus of this paper is how healthcare institutions can deal with euthanasia requests on an organizational level by means of a written institutional ethics policy. The general aim is to make a critical analysis whether these policies can be considered as organizational-ethical instruments that support healthcare institutions to take their institutional responsibility for (...) dealing with euthanasia requests. By means of an interpretative analysis, we conducted a process of reinterpretation of results of former Belgian empirical studies on written institutional ethics policies on euthanasia in dialogue with the existing international literature. The study findings revealed that legal regulations, ethical and care-oriented aspects strongly affected the development, the content, and the impact of written institutional ethics policies on euthanasia. Hence, these three cornerstones—law, care and ethics—constituted the basis for the empirical-based organizational-ethical framework for written institutional ethics policies on euthanasia that is presented in this paper. However, having a euthanasia policy does not automatically lead to more legal transparency, or to a more professional and ethical care practice. The study findings suggest that the development and implementation of an ethics policy on euthanasia as an organizational-ethical instrument should be considered as a dynamic process. Administrators and ethics committees must take responsibility to actively create an ethical climate supporting care providers who have to deal with ethical dilemmas in their practice. (shrink)

Given any proposition, is it possible to have rationally acceptable attitudes towards it? Absent reasons to the contrary, one would probably think that this should be possible. In this paper I provide a reason to the contrary. There is a proposition such that, if one has any opinions about it at all, one will have a rationally unacceptable set of propositional attitudes—or if one doesn’t, one will end up being cognitively imperfect in some other manner. The proposition I am concerned (...) with is a self-referential propositional attitude ascription involving the propositional attitude of rejection. Given a basic assumption about what constitutes irrationality, and a few assumptions about the nature of cognitively ideal agents, a paradox results. This paradox is superficially like the Liar, but it is importantly different in that no alethic notions are involved at all. As such, it stands independent of the Liar and is not a ‘revenge’ version of it. After setting out the paradox I discuss possible responses. After considering several I argue that one is best off simply accepting that the paradox shows us something surprising and interesting about rationality: that some cognitive shortfall is unavoidable even for ideal agents. I argue that nothing disastrous follows from accepting this conclusion. (shrink)

This paper presents and illustrates a formal logic for the abduction of singular hypotheses. The logic has a semantics and a dynamic proof theory that is sound and complete with respect to the semantics. The logic presupposes that, with respect to a specific application, the set of explananda and the set of possible explanantia are disjoint . Where an explanandum can be explained by different explanantia, the logic allows only for the abduction of their disjunction.

Detection of genetic aberrations in prenatal samples, obtained through amniocentesis or chorion villus biopsy, is increasingly performed using chromosomal microarray (CMA), a technique that can uncover both aneuploidies and copy number variants throughout the genome. Despite the obvious benefits of CMA, the decision on implementing the technology is complicated by ethical issues concerning variant interpretation and reporting. In Belgium, uniform guidelines were composed and a shared database for prenatal CMA findings was established. This Belgian approach sparks discussion: it is evidence-based, (...) prevents inconsistencies and avoids parental anxiety, but can be considered paternalistic. Here, we reflect on the cultural and moral bases of the Belgian reporting system of prenatally detected variants. (shrink)

Does the moral badness of pain depend on who feels it? A common, but generally only implicitly stated view, is that it does not. This view, ‘unitarianism’, maintains that the same interests of different beings should count equally in our moral calculus. Shelly Kagan’s project in How to Count Animals, more or less is to reject this common view, and develop an alternative to it: a hierarchical view of moral status, on which the badness of pain does depend on who (...) feels it. In this review essay, we critically examine Kagan’s argument for status hierarchy. In particular, we reject two of the central premises in his argument: that moral standing is ultimately grounded in agency and that unitarianism is overdemanding. We conclude that moral status may, despite Kagan’s compelling argument to the contrary, not be hierarchical. (shrink)

Grotius' Latin poetry is typical for its manifold reminiscences of examples from Roman antiquity. His favourite Latin poets were Lucan, Manilius, Statius and Claudian. Especially the influence of the first-mentioned poet is prominent. It is shown here by some examples from the Genealogia Nassaviorum , the Silva in Annales Borrhii and other poems in what way Grotius made use of Lucan.