This article discusses how inference to the best explanation (IBE) can be justified as a practical meta-argument. It is, firstly, justified as a practical argument insofar as accepting the best explanation as true can be shown to further a specific aim. And because this aim is a discursive one which proponents can rationally pursue in—and relative to—a complex controversy, namely maximising the robustness of one’s position, IBE can be conceived, secondly, as a meta-argument. My analysis thus bears a certain analogy (...) to Sellars’ well-known justification of inductive reasoning (Sellars, In: Essays in honour of Carl G. Hempel, 1969); it is based on recently developed theories of complex argumentation (Betz, In: Theorie dialektischer Strukturen, 2010a). (shrink)
We use recently developed approaches in argumentation theory in order to revamp the hypothetico-deductive model of confirmation, thus alleviating the well-known paradoxes the H-D account faces. More specifically, we introduce the concept of dialectic confirmation on the background of the so-called theory of dialectical structures (Betz 2010, 2012b). Dialectic confirmation generalises hypothetico-deductive confirmation and mitigates the raven paradox, the grue paradox, the tacking paradox, the paradox from conceptual difference, and the problem of surprising evidence.
Based on the theory of dialectical structures, I review the concept of degree of justification of a partial position a proponent may hold in a controversial debate. The formal concept of degree of justification dovetails with our pre-theoretic intuitions about a thesis' strength of justification. The central claim I'm going to defend in this paper maintains that degrees of justification, as defined within the theory of dialectical structures, correlate with a proponent position's verisimilitude. I vindicate this thesis with the results (...) of simulations of controversial argumentation. (shrink)
The ideal of value free science states that the justification of scientific findings should not be based on non-epistemic (e.g. moral or political) values. It has been criticized on the grounds that scientists have to employ moral judgements in managing inductive risks. The paper seeks to defuse this methodological critique. Allegedly value-laden decisions can be systematically avoided, it argues, by making uncertainties explicit and articulating findings carefully. Such careful uncertainty articulation, understood as a methodological strategy, is exemplified by the current (...) practice of the Intergovernmental Panel on Climate Change (IPCC). (shrink)
By means of multi-agent simulations, it investigates the truth and consensus-conduciveness of controversial debates. The book brings together research in formal epistemology and argumentation theory.
This paper gives an explication of our intuitive notion of strength of justification in a controversial debate. It defines a thesis' degree of justification within the bipolar argumentation framework of the theory of dialectical structures as the ratio of coherently adoptable positions according to which that thesis is true over all coherently adoptable positions. Broadening this definition, the notion of conditional degree of justification, i.e.\ degree of partial entailment, is introduced. Thus defined degrees of justification correspond to our pre-theoretic intuitions (...) in the sense that supporting and defending a thesis t increases, whereas attacking it decreases, t's degree of justification. Moreover, it is shown that (conditional) degrees of justification are (conditional) probabilities. Eventually, the paper explains that it is rational to believe theses with a high degree of justification insofar as this strengthens the robustness of one's position. (shrink)
This study investigates the ethical aspects of deploying and researching into so-called climate engineering methods, i.e. large-scale technical interventions in the climate system with the objective of offsetting anthropogenic climate change. The moral reasons in favour of and against R&D into and deployment of CE methods are analysed by means of argument maps. These argument maps provide an overview of the CE controversy and help to structure the complex debate.
Descartes' "Meditationen" sind vielleicht 'der' Klassiker der Philosophie. Sie behandeln grundlegende Fragen: Welche Arten von Gegenständen kommen in der Welt vor? Was für eine Art von Ding bin ich? Bin ich frei? Was ist Wahrheit? Welchen Status haben logische Wahrheiten oder mathematische Theoreme? Was kann ich wissen? Gregor Betz' systematischer Kommentar rekonstruiert die entsprechenden Gedankengänge und Begründungen und versucht Antworten auf Descartes' Fragen zu geben. Auch andere Philosophen, insbesondere des 20. Jahrhunderts, werden in einen Dialog mit Descartes gestellt. Denn eine (...) philosophische Position zu verstehen bedeutet letztlich auch zu überblicken, "welche weiteren Thesen sie impliziert und mit welchen anderen Positionen sie in Konflikt gerät", so der Autor des Bandes. (shrink)
In einer Welt, in der der Umgang mit Komplexität und Unsicherheit an Bedeutung gewinnt, sind politische Entscheidungsträger immer stärker auf eine wissenschaftliche Beratung angewiesen. Trotz des Bedarfs der politischen Akteure nach konkreten Handlungsempfehlungen sollte seriöse Politikberatung die grundlegenden Werte wissenschaftlichen Arbeitens nicht aus den Augen verlieren.
This paper investigates in how far a theory of dialectical structures sheds new light on the old problem of giving a satisfying account of the fallacy of petitio principii, or begging the question. It defends that (i) circular argumentation on the one hand and petitio principii on the other hand are two distinct features of complex argumentation, and that (ii) it is impossible to make general statements about the defectiveness of an argumentation that exhibits these features. Such an argumentation, in (...) contrast, has to be evaluated on a case-by-case basis. “Petitio principii”, this paper thence suggests, is one name for, in fact, a multitude of different and quite complex dialectical situations which require specific analysis and evaluation. (shrink)
Wo Meinungen aufeinanderprallen, um Verständnis geworben und Überzeugungsarbeit geleistet wird, sind Begründungen nicht weit. Für jede Überzeugung gibt es immer ein, zwei Gründe, die mit Gegengründen konfrontiert und, im Gegenzug, mit weiteren Überlegungen verteidigt werden usw. usf. Schnell sind wir verwirrt und drohen, ohne uns der "Grammatikregeln" vernünftigen Argumentierens zu besinnen, nicht mehr durchzublicken. Die Theorie dialektischer Strukturen leistet einen Beitrag zur Grammatik vernünftigen Argumentierens. Sie stellt Begriffe und Verfahren bereit, um Fragen, die sich angesichts einer komplexen Argumentation stellen können, (...) zu beantworten: Wie beziehen sich die einzelnen Argumente der Debatte aufeinander? Welche Positionen vertreten die verschiedenen Proponenten, und wie lassen sich diese bewerten? Wie gut ist die zentrale These der Kontroverse alles in allem begründet? Ist die und die Argumentationshandlung angesichts des Debattenstandes tatsächlich zweckmäßig und rational? Liegt hier eine zirkuläre - und damit fehlerhafte - Argumentation vor? Die klassische Logik, die sogenannte informal logic und argumentationstheoretische Ansätze der Künstlichen Intelligenz bilden Anknüpfungspunkte der Theorie dialektischer Strukturen. Exemplarisch werden die entwickelten argumentationstheoretischen Methoden zur Analyse umfangreicher philosophischer Kontroversen eingesetzt. (shrink)
Frank Knight (1921) famously distinguished the epistemic modes of certainty, risk, and uncertainty in order to characterize situations where deterministic, probabilistic or possibilistic foreknowledge is available. Because our probabilistic knowledge is limited, i.e. because many systems, e.g. the global climate, cannot be described and predicted probabilistically in a reliable way, Knight's third category, possibilistic foreknowledge, is not simply swept by the probabilistic mode. This raises the question how to justify possibilistic predictionsincluding the identi cation of the worst case. The development of (...) such a modal methodology is particularly vital with respect to predictions of climate change. I show that a methodological dilemma emerges when possibilistic predictions are framed in traditional terms and argue that a more nuanced conceptual framework, distinguishing dierent types of possibility, should be used in order to convey our uncertain knowledge about the future. The new conceptual scheme, however, questions the applicability of standard rules of rational decision-making, thus generating new challenges. (shrink)
This paper develops concepts and procedures for the evaluation of complex debates. They provide means for answering such questions as whether a thesis has to be considered as proven or disproven in a debate or who carries a burden of proof. While being based on classical logic, this framework represents an (argument-based) approach to non-monotonic, or defeasible reasoning. Debates are analysed as dialectical structures, i.e. argumentation systems with an attack- as well as a support-relationship. The recursive status assignment over the (...) arguments is conditionalised on proponents in a debate. The problem of multiple status assignments arising on circular structures is solved by showing that uniqueness can be guaranteed qua reconstruction of a debate. The notion of burden of proof as well as other discursive aims rational proponents pursue in a debate is defined within the framework. (shrink)
As climate policy decisions are decisions under uncertainty, being based on a range of future climate change scenarios, it becomes a crucial question how to set up this scenario range. Failing to comply with the precautionary principle, the scenario methodology widely used in the Third Assessment Report of the International Panel on Climate Change (IPCC) seems to violate international environmental law, in particular a provision of the United Nations Framework Convention on Climate Change. To place climate policy advice on a (...) sound methodological basis would imply that climate simulations which are based on complex climate models had, in stark contrast to their current hegemony, hardly an epistemic role to play in climate scenario analysis at all. Their main function might actually consist in ‘foreseeing future ozone-holes’. In order to argue for these theses, I explain first of all the plurality of climate models used in climate science by the failure to avoid the problem of underdetermination. As a consequence, climate simulation results have to be interpreted as modal sentences, stating what is possibly true of our climate system. This indicates that climate policy decisions are decisions under uncertainty. Two general methodological principles which may guide the construction of the scenario range are formulated and contrasted with each other: modal inductivism and modal falsificationism. I argue that modal inductivism, being the methodology implicitly underlying the third IPCC report, is severely flawed. Modal falsificationism, representing the sound alternative, would in turn require an overhaul of the IPCC practice. (shrink)
Climate policy decisions are decisions under uncertainty and are, therefore, based on a range of future climate scenarios, describing possible consequences of alternative policies. Accordingly, the methodology for setting up such a scenario range becomes pivotal in climate policy advice. The preferred methodology of the Intergovernmental Panel on Climate Change will be characterised as ,,modal verificationism"; it suffers from severe shortcomings which disqualify it for scientific policy advice. Modal falsificationism, as a more sound alternative, would radically alter the way the (...) climate scenario range is set up. Climate science's inability to find robust upper bounds for future temperature rise in line with modal falsificationism does not disprove that methodology, rather, this very fact prescribes even more drastic efforts to curb CO2 emissions than currently proposed. (shrink)
The Stern Review on The Economics of Climate Change is a highly influential welfare analysis of climate policy measures which has been published in 2006. This paper identifies and systematically assesses the long-term socioeconomic and climatic predictions the Stern Review relies on, and reflects them philosophically. Being a cost-benefit analysis, the Stern Review has to predict the benefits of climate mitigation policies, i.e.the damaging consequences of climate change which might be avoided, as well as the costs of implementing such policies. (...) While distinguishing deterministic, probabilistic, and possibilisitic forecasts, this paper finds that the Review's major predictions severly suffer from a lack of robustness. It argues, moreover, that the use of subjective probabilities as well as the fact/value entanglement pose additional problems. Given our ignorance, this assessment raises finally the question how detailed an analysis of climate policy decisions should reasonably be at all, and whether the argument for acting against climate change is maybe very simple. (shrink)
This paper shows how complex argumentation, analyzed as dialectical structures, can be evaluated within a Bayesian framework by interpreting them as coherence constraints on subjective degrees of belief. A dialectical structure is a set of arguments (premiss-conclusion structure) among which support- and attack-relations hold. This approach addresses the observation that some theses in a debate can be better justified than others and thus fixes a shortcoming of a theory of defeasible reasoning which applies the bivalence principle to argument evaluations by (...) assigning them the status of being either defeated or undefeated. Evaluation procedures which are based on the principle of bivalence can, however, be embedded as a special case within the Bayesian framework. The approach developed in this paper rests on the assumptions that arguments can be reconstructed as deductively valid and that complex argumentation can be reconstructed such that premisses of arguments with equivalent conclusions are pairwise independent. (shrink)
Gregor Betz explores the following questions: Where are the limits of economics, in particular the limits of economic foreknowledge? Are macroeconomic forecasts credible predictions or mere prophecies and what would this imply for the way economic policy decisions are taken? Is rational economic decision making possible without forecasting at all?
This article sets up a graph-theoretical framework for argumentation-analysis (dialectical analysis) which expands classical argument-analysis. Within this framework, a main theorem on the existence of inconsistencies in debates is stated and proved: the vicious circle theorem. Subsequently, two corollaries which generalize the main theorem are derived. Finally, a brief outlook is given on further expansions and possible applications of the developed framework.
Dieser Beitrag diskutiert Oskar Morgensterns These von der Unmöglichkeit von Wirtschaftsprognose. Nach einer kritischen Rekonstruktion Morgensterns Argumente wird diese These in ihrer starken, apriorischen Lesart zurückgewiesen. Demgegenüber gestatten es die Ergebnisse empirischer Prognoseevaluationen, Morgensterns Überlegungen als kontingente Erklärungen des Scheiterns makroökonomischer Vorhersagen umzuinterpretieren. Der Beitrag schließt deshalb mit einer provokanten Konklusion, die bereits Morgenstern zog: der Forderung, Versuche makroökonomischer Vorhersage einzustellen.
