Is there any argument for scepticism? The epistemic problem of the possibility of error. Arguments for scepticism rest on the assumption that knowledge claims are fallible. For this reason the concept of knowledge appears to be questionable. Since it is necessary to distinguish doubts from possible doubts, the arguments for scepticism appear to be unconvincing. If we take it into account that we know something that is immune to doubt, we should draw the conclusion that, contrary to scepticism, knowledge claims (...) have to be compatible with being fallible. Thus any knowledge claim is capable of being doubted. (shrink)

Summary Influenced by the account of K. Popper and, moreover, of C. G. Hempel and P. Oppenheim, it is generally assumed, that a prediction can be logically deduced from hypotheses, i. e. lawlike propositions, and initial conditions. It is not clear, in which respect a prediction can correctly be supposed to be a proposition which is either true or false. From a logical point of view, serious difficulties arise in assuming that the deductive-nomological model consists of a valid argument. Further (...) objections to this account are developed with regard to lawlike propositions. Since a lawlike proposition is — by definition — not true or definitely true, but only supposed to be true, it cannot function as a true premise among other true premises for the purpose of deduction. Special difficulties arise with regard to predictions: A predictive argument does not give any reason for the truth of the predictionK, but only — if at all — for the prediction of the truth ofK. In the latter case, the conclusion K clearly does not consist of a proposition (which could be either true or false) but rather of a predicting proposition. (shrink)

It seems that actions are perceived from two different perspectives: on the one hand by the agent of the action and on the other hand by the observer. The latter perspective appears to be more reliable because of inter-subjective observations. Hence, determinists argue that actions can be causally explained by events, whereas the indeterminists claim that actions are acausal events. If e.g. Mary opens the door, we observe her behaviour but not her action; for it is not clear to us (...) from our observations whether she intends to open the door, whether she opens the door unconsciously or whether she opens the door only accidentally when sleepwalking. Since actions do not consist in events, their observations involve behaviouristic fallacy. Consequently, deterministic as well as indeterministic arguments prove to be untenable. Since only the first perspective, i.e. that of the agent, remains, it is necessary to refer to the reports about their actions and to our observations of their behaviour when explicating the concept of action. This enables us to clarify the question of how far human beings are free to do, or not to do, what they want. (shrink)

Goethe's objections to Newton's theory of light and colours are better than often acknowledged. You can accept the most important elements of these objections without disagreeing with Newton about light and colours. As I will argue, Goethe exposed a crucial weakness of Newton's methodological self-assessment. Newton believed that with the help of his prism experiments, he could prove that sunlight was composed of variously coloured rays of light. Goethe showed that this step from observation to theory is more problematic than (...) Newton wanted to admit. By insisting that the step to theory is not forced upon us by the phenomena, Goethe revealed our own free, creative contribution to theory construction. And Goethe's insight is surprisingly significant, because he correctly claimed that all of the results of Newton's prism experiments fit a theoretical alternative equally well. If this is correct, then by suggesting an alternative to a well-established physical theory, Goethe developed the problem of underdete... (shrink)

Artificiell intelligens (AI) är ett ungt forskningsområde där många av de grundläggande problemen förefaller att vara av filosofisk art.1 Ämnet har sina filosofiska rötter dels i traditionen från Leibniz, Frege, Russell och Hilbert, som strävar efter att formalisera principerna för exakt tänkande, dels i den klassiska mekanismen: idén att människan är en maskin och att det mänskliga tänkandet är en mekanisk process. Som en första approximation kan vi säga att AI är det vetenskapliga studiet av hur man konstruerar och bygger (...) maskiner (datorer) som är intelligenta (eller uppvisar intelligent beteende). Det är lätt att se att denna forskning aktualiserar frågor av filosofiskt slag. Hit hör problem som rör tänkandets natur samt förhållandet mellan medvetandet och kroppen. Inom AI ses ofta datorns arbetssätt som en modell för människans kognitiva processer och man föreställer sig kanske att hjärnan är ett slags dator. Eftersom hjärnan liknas vid en dator och en dator tänks arbeta rent mekaniskt i enlighet med ett givet program (en given algoritm), så föreställer man sig att samma sak bör gälla för hjärnan. Analogin hjärna-dator leder till föreställningen att tänkande inte är något annat än en dators mekaniska manipulerande av symboler i enlighet med givna formella regler. Denna uppfattning om tänkandets natur förefaller samtidigt problematisk: mekanisk manipulation av symboler förutsätter ingen förståelse av symbolernas innebörd; genuint tänkande, å andra sidan, tycks förutsätta sådan förståelse. Ibland verkar också analogin hjärna-dator i den motsatta riktningen. Eftersom hjärnan liknas vid en dator och hjärnan har en mental dimension, så föreställer man sig kanske att samma sak måste gälla för vissa datorer: synen på hjärnan som en dator leder till tanken att det borde vara möjligt att konstruera datorer som bokstavligen tänker, känner och förnimmer. Man föreställer sig kanske att man skall kunna konstruera ett artificiellt medvetande. Vi är alla förtrogna med datorer som (i en viss mening) kan lösa förelagda uppgifter på ett intelligent sätt, men följer det därav att dessa datorer kan tänka? Inte tänker väl en schackspelande dator på schack? Hur intelligent dagens datorer än beter sig, så verkar det ändå inte rimligt att säga att de har tankar, känslor eller upplevelser. Men kan man utesluta att vi någon gång i framtiden kommer att kunna konstruera datorer som verkligen förstår, är medvetna, och tänker? Dessa frågor rymmer många begreppsliga oklarheter. Vad är intelligens, tänkande, förståelse, medvetande? Hur förhåller sig intelligens och tänkande till medvetandets fenomenella sida: upplevelser och känslor? Om vad slags ting är det meningsfullt att säga att de har intelligens, medvetande, mentala tillstånd, etc.? Är det meningsfullt att säga detta om en hjärna, en maskin, en dator? Vad menas med en maskin (dator)? Hur kan vi veta (avgöra) om ett ting har intelligens, tankar, känslor eller upplevelser? I denna uppsats avser vi att närmare belysa sambandet mellan filosofi och AI samt kritiskt granska några av AI-forskningens förutsättningar inom filosofi och logik. (shrink)

The book is an introductory exposition of the development of the physical and astronomical notions of the universe. It covers the period from Greek antiquity to the Copernican revolution and the Renaissance, half of the text being devoted to medieval science within both the Aristotelian and the Archimedean traditions. The book is intended for a general audience interested in intellectual and scientific developments, but should also be useful as a guide to further studies. Thus it has an extensive bibliography classifying (...) much of the secondary literature on the subject, and also a sixty page 'dictionary' of all the scientists and philosophers mentioned in the text. This contains references to printed editions of the sources and to a selection of books and periodicals. (shrink)

In the late summer of 1998, the authors, a cognitive scientist and a logician, started talking about the relevance of modern mathematical logic to the study of human reasoning, and we have been talking ever since. This book is an interim report of that conversation. It argues that results such as those on the Wason selection task, purportedly showing the irrelevance of formal logic to actual human reasoning, have been widely misinterpreted, mainly because the picture of logic current in psychology (...) and cognitive science is completely mistaken. We aim to give the reader a more accurate picture of mathematical logic and, in doing so, hope to show that logic, properly conceived, is still a very helpful tool in cognitive science. The main thrust of the book is therefore constructive. We give a number of examples in which logical theorizing helps in understanding and modeling observed behavior in reasoning tasks, deviations of that behavior in a psychiatric disorder (autism), and even the roots of that behavior in the evolution of the brain. (shrink)

When governments introduce controversial policies or face a risk of policy failure, officeholders try to avoid blame and justify their decisions by using various legitimation strategies. This paper focuses on the ways in which legitimations are expressed in government social media communication, using the Twitter posts of the British government’s Brexit department as an example. We show how governments may seek legitimacy by appealing to (1) the personal authority of individual policymakers, (2) the collective authority of (political) organisations, (3) the (...) impersonal authority of rules or documents, (4) the goals or effects of government policy, (5) ‘the will of the people’, and (6) time pressure. The results suggest that official legitimations in social media posts tend to rely more on references to authority and shared values rather than presentation of evidence and sound arguments. (shrink)

We discuss external and internal graphical and linguistic representational systems. We argue that a cognitive theory of peoples' reasoning performance must account for (a) the logical equivalence of inferences expressed in graphical and linguistic form, and (b) the implementational differences that affect facility of inference. Our theory proposes that graphical representation limit abstraction and thereby aid “processibility”. We discuss the ideas of specificity and abstraction, and their cognitive relevance. Empirical support both comes from tasks which involve the manipulation of external (...) graphics and tasks that do not. For the former, we take Euler's (1772) circles, provide a novel computational reconstruction, show how it captures abstractions, and contrast it with earlier construals and with Johnson‐Laird's (1983) mental models representations. We demonstrate equivalence of the graphical Euler system, and the nongraphical mental models system. For tasks not involving manipulation of external graphics, we discuss text comprehension, and the mental performance of syllogisms. By positing an internal system with the same specificity as Euler's circles, we cover the mental models data, and generate new empirical predictions. Finally, we consider how the architecture of working memory explains why such specific representations are relatively easy to store. (shrink)

Pacifists and their opponents disagree not only about moral questions, but rather often about factual questions as well—as seen when looking at the controversy surrounding the crisis in Kosovo. According to my reconstruction of pacifism, this is not surprising since the pacifist,legitimately, looks at the facts in the light of her system of value. Her opponent, in turn, looks at the facts in the light of an alternative value system, and the quarrel between the two parties about supposedly descriptive matters (...) never ceases, as there is no objective reality about the war in question that could settle the issue.In my view, the pacifist's value-laden way of looking at reality implicitly obeys three epistemic imperatives. First, the Epistemic Imperative concerning Human Nature ("Resist demonizing the other side; always try to understand the case from the other point of view"). Second, the Epistemic Imperative concerning Non-Violent Alternatives ("Always search for non-violent alternatives to military action"). Third, the Epistemic Imperative concerning Uncontrolled Escalation ("Hone your senses to the uncontrolled, irreversible side effects of military action, particularly to the danger of military escalation leading to another world war"). Objective reality has no way of telling us how far we should go in following these imperatives. Rather, we have to make the decision about how far we are going to take them ourselves. In this way, the pacifist's epistemic imperatives are comparable to Kant's regulative principles. (shrink)

The search for causes of perinatal brain damage needs a solid theoretical foundation. Current theory apparently does not offer a unanimously accepted view of what constitutes a cause, and how it can be identified. We discuss nine potential theoretical misconceptions: (1) too narrow a view of what is a cause (causal production vs. facilitation), (2) extrapolating from possibility to fact (potential vs. factual causation), (3) if X, then invariably Y (determinism vs. probabilism), (4) co-occurrence in individuals vs. association in populations, (...) (5) one cause is all that is needed (single cause attribution vs. multicausal constellations), (6) drawing causal inferences from very small numbers of observations (the tendency to generalize), (7) unstated causal inferences, (8) ignoring heterogeneity, and (9) failing to consider alternative explanations for what is observed. We hope that our critical discussion will contribute to fruitful research and help reduce the burden of perinatal brain damage. (shrink)

Theoria, Volume 88, Issue 3, Page 494-528, June 2022.

We advance a theoretical framework which combines recent insights of research in logic, psychology, and formal semantics, on the nature of diagrammatic representation and reasoning. In particular, we wish to explain the varied efficacy of reasoning and representing with diagrams. In general we consider diagrammatic representations to be restricted in expressive power, and we wish to explain efficacy of reasoning with diagrams via the semantical and computational properties of such restricted `languages'. Connecting these foundational insights (from semantics and complexity theory) (...) to the psychology of reasoning with diagrams requires us to develop the notion of the {\it availability} (to an agent) of {\it constraints} operating within representation systems, as a consequence of their direct semantic interpretation. Thus we offer a number of fundamental definitions as well as a research programme which aligns current efforts in the logical and psychological analysis of diagrammatic representation systems. (shrink)

Nach Morton White können wir die holistische Quine/Duhem-These auf ethische Sätze genauso anwenden wie auf wissenschaftliche. Demzufolge mögen sich die meisten ethische Sätze zwar nicht einzeln testen lassen, wohl aber im Zusammenhang einer kompletten Theorie, die sowohl deskriptive als auch normative Sätze enthält. Ich diskutiere zwei Vorschläge dafür, wie dieser Vergleich durchbuchstabiert werden könnte. Laut Whites eigenem Vorschlag lassen sich einige normative Konsequenzen des Gesamtsystems durch Konfrontation mit den emotionalen Reaktionen des Sprechers testen. Laut meinem Vorschlag sind einige normative Konsequenzen (...) des Systems bereits Beobachtungssätze in Quines Sinn und können genauso getestet werden wie naturwissenschaftliche Beobachtungssätze, nämlich durch Sinneserfahrung. Kurzum, es gibt moralische Beobachtungssätze. Quine bezeichnet diejenigen Sätze als Beobachtungssätze, die alle anwesenden Sprecher einer Gemeinschaft stets gleich beurteilen und die der einzelne Sprecher ausschließlich aufgrund momentaner Sinnesreizung bejaht oder verneint (also unabhängig von Hintergrund-Informationen). In Quines Argument gegen moralische Beobachtungssätze steckt folgender Fehler: Quine glaubt, dass sich moralische Fragen immer nur angesichts von Hintergrund-Informationen beurteilen lassen. Bei vielen moralischen Sätzen mag das so sein; aber es gibt Gegenbeispiele, in denen Hintergrund-Informationen ausgeschaltet sind, z.B. "Dies ist sichtbares Unrecht". (shrink)

First Published in 1999. Routledge is an imprint of Taylor & Francis, an informa company.

Theory of illness causation is an important issue in all biomedical sciences, and solid etiological explanations are needed in order to develop therapeutic approaches in medicine and preventive interventions in public health. Until now, the literature about the theoretical underpinnings of illness causation research has been scarce and fragmented, and lacking a convenient summary. This interdisciplinary book provides a convenient and accessible distillation of the current status of research into this developing field, and adds a personal flavor to the discussion (...) by proposing the etiological stance as a comprehensive approach to identify modifiable causes of illness. (shrink)

Epistemic conditionals have often been thought to satisfy the Ramsey test : If A, then B is acceptable in a belief state G if and only if B should be accepted upon revising G with A. But as Peter Gärdenfors has shown, RT conflicts with the intuitively plausible condition of Preservation on belief revision. We investigate what happens if RT is retained while Preservation is weakened, or vice versa. We also generalize Gärdenfors' approach by treating belief revision as a relation (...) rather than as a function.In our semantic approach, the same relation is used to model belief revision and to give truth-conditions for conditionals. The approach validates a weak version of the Ramsey Test — essentially, a restriction of RT to maximally consistent belief states. (shrink)

Learning with different kinds of ICT-based tools is an important issue in today's society. In this article we focus on how design of technology rich environments based on state of the art learning principles can give us new insights about how learning occur, and how we can develop new types of learning environments. Medical education constitutes the subject domain. There has been a considerable effort to develop 3D technologies in this field, and the article provides a careful review of how (...) these technologies are applied. There is, however, a substantial gap between these advances and the use of technologies in medical education. Related work proposes individualistic assumptions or metaphors that do not focus explicitly on learning and technology mediation. Based on theoretical analysis of previous literature in the field we argue that there is a need for a new unit of analysis that includes the relationship between individual and collective activity and the role of technology herein. The socio-cultural and especially activity theory is taken as the perspective which gives the possibility to develop the argumentation about the unit of analysis. The unit of analysis also has implications for design of 3D environments. The design principles are elaborated upon and examples are given in relation to an application called Matador (Medical Advanced Training in an Artificial Distributed Environment). Matador is aimed at developing a simulation environment for training in emergency medicine. (shrink)

Executive function has become an important concept in explanations of psychiatric disorders, but we currently lack comprehensive models of normal executive function and of its malfunctions. Here we illustrate how defeasible logical analysis can aid progress in this area. We illustrate using autism and attention deficit hyperactivity disorder (ADHD) as example disorders, and show how logical analysis reveals commonalities between linguistic and non-linguistic behaviours within each disorder, and how contrasting sub-components of executive function are involved across disorders. This analysis reveals (...) how logical analysis is as applicable to fast, automatic and unconscious reasoning as it is to slow deliberate cogitation. (shrink)

Festschrift for Michiel van Lambalgen on the occasion of his retirement as professor of logic and cognitive science at the University of Amsterdam.

Quine claims that holism (i.e., the Quine-Duhem thesis) prevents us from defining synonymy and analyticity (section 2). In "Word and Object," he dismisses a notion of synonymy which works well even if holism is true. The notion goes back to a proposal from Grice and Strawson and runs thus: R and S are synonymous iff for all sentences T we have that the logical conjunction of R and T is stimulus-synonymous to that of S and T. Whereas Grice and Strawson (...) did not attempt to defend this definition, I try to show that it indeed gives us a satisfactory account of synonymy. Contrary to Quine, the notion is tighter than stimulus-synonymy -- particularly when applied to sentences with less than critical semantic mass (section 3). Now according to Quine, analyticity could be defined in terms of synonymy, if synonymy were to make sense: A sentence is analytic iff synonymous to self-conditionals. This leads us to the following notion of analyticity: S is analytic iff, for all sentences T, the logical conjunction of S and T is stimulus-synonymous to T; an analytic sentence does not change the semantic mass of any theory to which it may be conjoined (section 4). This notion is tighter than Quine's stimulus-analyticity; unlike stimulus-analyticity, it does not apply to those sentences from the very center of our theories which can be assented to come what may, even though they are not synthetic in the intuitive sense (section 5). (shrink)

The objective of our article is to show how “quality of evidence” and “imprecision,” as they are defined in Grading of Recommendations Assessment, Development, and Evaluation articles, may lead to confusion. We focus only on the context of systematic reviews.