It is controversial whether Wittgenstein's philosophy of mathematics is of critical importance for mathematical proofs, or is only concerned with the adequate philosophical interpretation of mathematics. Wittgenstein's remarks on the infinity of prime numbers provide a helpful example which will be used to clarify this question. His antiplatonistic view of mathematics contradicts the widespread understanding of proofs as logical derivations from a set of axioms or assumptions. Wittgenstein's critique of traditional proofs of the infinity of prime numbers, specifically those of (...) Euler and Euclid, not only offers philosophical insight but also suggests substantive improvements. A careful examination of his comments leads to a deeper understanding of what proves the infinity of primes. (shrink)
Ethical thought experiments such as the trolley dilemma have been investigated extensively in the past, showing that humans act in utilitarian ways, trying to cause as little overall damage as possible. These trolley dilemmas have gained renewed attention over the past few years, especially due to the necessity of implementing moral decisions in autonomous driving vehicles. We conducted a set of experiments in which participants experienced modified trolley dilemmas as drivers in virtual reality environments. Participants had to make decisions between (...) driving in one of two lanes where different obstacles came into view. Eventually, the participants had to decide which of the objects they would crash into. Obstacles included a variety of human-like avatars of different ages and group sizes. Furthermore, the influence of sidewalks as potential safe harbors and a condition implicating self-sacrifice were tested. Results showed that participants, in general, decided in a utilitarian manner, sparing the highest number of avatars possible with a limited influence by the other variables. Derived from these findings, which are in line with the utilitarian approach in moral decision making, it will be argued for an obligatory ethics setting implemented in ADVs. (shrink)
In this paper I problematize the use of appeals to the common intuitions people have about the morality of our society’s current treatment of animals in order to defend that treatment. I do so by looking at recent findings in the field of cognitive science. First I will examine the role that appeals to common intuition play in philosophical arguments about the moral worth of animals, focusing on the work of Carl Cohen and Richard Posner. After describing the theory of (...) Moral Disengagement—which has been used to explain how people live with themselves when they commit acts that they themselves believe are wrong—I will review the recent empirical research that details the nature of the moral disengagement that accompanies animal treatment. This includes studies that reveal that those who eat animals engage in the following behaviors: They minimize the nature of the harm of killing animals by casting the practice in a positive light; They obscure personal responsibility by blaming others for harms; They minimize the effect of the conduct on the animals by avoiding reference to the animal origins of meat; They derogate vegetarians as a way of avoiding feelings of guilt for their own practices. Perhaps most importantly, a number of empirical studies have shown that people’s intuitions about the moral worth of animals are shaped by their practice of eating animals—and not the other way around. In addition to the studies on moral disengagement, there is another body of research that has attempted to discover what accounts for the individual differences in attitudes people have toward the moral worth of animals. These studies have linked masculinity and traits like Authoritarianism, Social Dominance Orientation and Right Wing Authoritarianism to the tendency to disregard the moral worth of animals. I will briefly summarize this body of research and will then conclude by arguing that this data should cause us to be highly skeptical of the value that the common intuition that people who eat animals have about the moral status of animals may have in helping us understand the actual moral worth of animals. (shrink)
O presente artigo tem como objetivo evidenciar as contribuições da História Oral como um importante caminho metodológico para os estudos das culturas escolares. Para tanto, o texto inicia discutindo as mudanças ocorridas no campo da História, que deram voz aos sujeitos do cotidiano. Em seguida o conceito de culturas escolares é entrelaçado à História Oral, sendo abordada como uma das possibilidades para recuperar os registros do passado através da subjetividade dos sujeitos de hoje. O artigo é concluído através de uma (...) reflexão sobre as contribuições desta abordagem metodológica para a História da Educação e os estudos das culturas escolares, bem como sinalizando a importância de os agentes da escola perceberem-se como protagonistas da história, questionando certezas, dualidades, a fim de colaborar na compreensão da sua construção sociocultural, bem como dos espaços em que atuam. (shrink)
Packed with ideas designed to help children learn to sing, this booklet offers criteria for selecting songs, strategies to bring out the best in children's voices, and suggestions for games, ideas, and resources.
This book addresses the implications of Richard Rorty’s rejection of experience. The author argues that there are ways to recover a concept of experience that is consistent with Rorty’s preference for a linguistic style of pragmatism.
This article identifies problems with regard to providing criteria that regulate the matching of logical formulae and natural language. We then take on to solve these problems by defining a necessary and sufficient criterion of adequate formalization. On the basis of this criterion we argue that logic should not be seen as an ars iudicandi capable of evaluating the validity or invalidity of informal arguments, but as an ars explicandi that renders transparent the formal structure of informal reasoning.
Newton claims to have proven the heterogeneity of light through his experimentum crucis. However, Olaf Müller has worked out in detail Goethe’s idea that one could likewise prove the heterogeneity of darkness by inverting Newton’s famous experiment. Müller concludes that this invalidates Newton’s claim of proof. Yet this conclusion only holds if the heterogeneity of light and the heterogeneity of darkness is logically incompatible. This paper shows that this is not the case. Instead, in Quine’s terms, we have two logically (...) compatible theories based on mutually irreducible theoretical terms. From a Quinean point of view, this does no harm to the provability of the corresponding statements. (shrink)
In §8 of Remarks on the Foundations of Mathematics (RFM), Appendix 3 Wittgenstein imagines what conclusions would have to be drawn if the Gödel formula P or ¬P would be derivable in PM. In this case, he says, one has to conclude that the interpretation of P as “P is unprovable” must be given up. This “notorious paragraph” has heated up a debate on whether the point Wittgenstein has to make is one of “great philosophical interest” revealing “remarkable insight” in (...) Gödel’s proof, as Floyd and Putnam suggest (Floyd (2000), Floyd (2001)), or whether this remark reveals Wittgenstein’s misunderstanding of Gödel’s proof as Rodych and Steiner argued for recently (Rodych (1999, 2002, 2003), Steiner (2001)). In the following the arguments of both interpretations will be sketched and some deficiencies will be identified. Afterwards a detailed reconstruction of Wittgenstein’s argument will be offered. It will be seen that Wittgenstein’s argumentation is meant to be a rejection of Gödel’s proof but that it cannot satisfy this pretension. (shrink)
According to some scholars, such as Rodych and Steiner, Wittgenstein objects to Gödel’s undecidability proof of his formula $$G$$, arguing that given a proof of $$G$$, one could relinquish the meta-mathematical interpretation of $$G$$ instead of relinquishing the assumption that Principia Mathematica is correct. Most scholars agree that such an objection, be it Wittgenstein’s or not, rests on an inadequate understanding of Gödel’s proof. In this paper, I argue that there is a possible reading of such an objection that is, (...) in fact, reasonable and related to Gödel’s proof. (shrink)
In philosophical contexts, logical formalisms are often resorted to as a means to render the validity and invalidity of informal arguments formally transparent. Since Oliver and Massey , however, it has been recognized in the literature that identifying valid arguments is easier than identifying invalid ones. Still, any viable theory of adequate logical formalization should at least reliably identify valid arguments. This paper argues that accounts of logical formalization as developed by Blau and Brun do not meet that benchmark. The (...) paper ends by suggesting different strategies to remedy the problem. (shrink)
In contrast to Hintikka’s enormously complex distributive normal forms of first- order logic, this paper shows how to generate minimized disjunctive normal forms of first-order logic. An effective algorithm for this purpose is outlined, and the benefits of using minimized disjunctive normal forms to explain the truth conditions of propo- sitions expressible within pure first-order logic are presented.
In his early philosophy as well as in his middle period, Wittgenstein holds a purely syntactic view of logic and mathematics. However, his syntactic foundation of logic and mathematics is opposed to the axiomatic approach of modern mathematical logic. The object of Wittgenstein’s approach is not the representation of mathematical properties within a logical axiomatic system, but their representation by a symbolism that identifies the properties in question by its syntactic features. It rests on his distinction of descriptions and operations; (...) its aim is to reduce mathematics to operations. This paper illustrates Wittgenstein’s approach by examining his discussion of irrational numbers. (shrink)
Es wird gezeigt, dass Wittgenstein in seiner Frühphilosophie ein nicht-axiomatisches Beweisverständnis entwickelt, für das sich das Problem der Begründung der Axiome nicht stellt. Nach Wittgensteins Beweisverständnis besteht der Beweis einer formalen Eigenschaft einer Formel – z.B. der logischen Wahrheit einer prädikatenlogischen Formel oder der Gleichheit zweier arithmetischer Ausdrücke – in der Transformation der Formel in eine andere Notation, an deren Eigenschaften sich entscheiden lässt, ob die zu beweisende formale Eigenschaft besteht oder nicht besteht. Dieses Verständnis grenzt Wittgenstein gegenüber einem axiomatischen (...) Beweisverständnis ab. Sein Beweisverständnis bedingt ein Programm der Grundlegung der Mathematik, das eine Alternative zu den Ansätzen des Logizismus, Formalismus und Konstruktivismus darstellt. Wittgensteins Ansatz steht im Widerspruch zu den Ergebnissen der Metamathematik, da er die Möglichkeit der Formulierung von Entscheidungsverfahren in der Prädikatenlogik und Arithmetik voraussetzt. Um seinem Ansatz gegenüber der traditionellen Metamathematik Recht zu geben, müsste gezeigt werden, dass sein Beweisverständnis im Bereich der Logik und Arithmetik – der traditionellen Metamathematik zum Trotz – realisierbar ist. (shrink)
This paper argues for a physicalistic interpretation of Wittgenstein's Tractatus Logico-Philosophicus. Wittgenstein's general conception of world and language analysis is interpreted and exemplified in relation to the historical background of the psychophysical analysis of sense data and, in particular, color analysis. Three of his main principles of analysis—the principle of independence, the context principle and the principle of atomism—are interpreted and justified on the background of physicalism. From his proof of color exclusion in the Tractatus, it is shown that Wittgenstein (...) had a detailed conception of how philosophy should fulfil the task of distinguishing between sense and nonsense using physicalistic presuppositions. (shrink)
Das Buch entwickelt einen neuartigen, physikalistischen Interpretationsansatz zu Wittgensteins Tractatus Logico-Philosophicus. Das traditionelle Urteil, Wittgenstein habe im Tractatus keine klare Vorstellung der Analyse gehabt, wird widerlegt. Auf der Basis der Rekonstruktion der um die Jahrhundertwende etablierten Sinnesdatenanalysen im allgemeinen und der Farbanalysen im besonderen wird nachgewiesen, daß Wittgensteins Tractatus eine physikalische Sinnesdatenanalyse voraussetzt. Auf diesem Hintergrund werden Wittgensteins allgemeine Auffassungen zur Analyse der Welt und Sprache gedeutet, begründet und exemplifiziert. Der Tractatus liefert die philosophische Klärung des mechanistischen Weltbildes von Boltzmann (...) und Hertz. Er stellt die Mittel bereit, um den Sinn der Sätze zu analysieren und die logische Zulässigkeit von Aussagen zu prüfen. Die Anwendung dieser Mittel ist Aufgabe der Philosophie. Daß sie anwendbar sind und wie sie anzuwenden sind, demonstriert dieses Buch. (shrink)
This paper describes a decision procedure for disjunctions of conjunctions of anti-prenex normal forms of pure first-order logic (FOLDNFs) that do not contain V within the scope of quantifiers. The disjuncts of these FOLDNFs are equivalent to prenex normal forms whose quantifier-free parts are conjunctions of atomic and negated atomic formulae (= Herbrand formulae). In contrast to the usual algorithms for Herbrand formulae, neither skolemization nor unification algorithms with function symbols are applied. Instead, a procedure is described that rests on (...) nothing but equivalence transformations within pure first-order logic (FOL). This procedure involves the application of a calculus for negative normal forms (the NNF-calculus) with A -||- A & A (= &I) as the sole rule that increases the complexity of given FOLDNFs. The described algorithm illustrates how, in the case of Herbrand formulae, decision problems can be solved through a systematic search for proofs that reduce the number of applications of the rule &I to a minimum in the NNF-calculus. In the case of Herbrand formulae, it is even possible to entirely abstain from applying &I. Finally, it is shown how the described procedure can be used within an optimized general search for proofs of contradiction and what kind of questions arise for a &I-minimal proof strategy in the case of a general search for proofs of contradiction. (shrink)
This paper illustrates what a philosophical and a logical investigation of colors amounts to in contrast to other kinds of color analysis such as physical, physiological, chemical, psychological or cultural analysis of colors. Neither a philosophical nor a logical analysis of colors is concerned with specific aspects of colors. Rather, these kinds of color analysis are concerned with what one might call “logical foundations of color theory”. I will illustrate this first by considering philosophical and then logical analysis of colors.
Anhand der genaueren Analyse von Newtons experimentum crucis und der Argumentation, die er auf dieses Experiment stützt, sowie Goethes Kritik hieran sollen im Folgenden zwei verbreitete Vorurteile revidiert werden: -/- 1. Newton ist kein Dogmatiker, der methodische Ansprüche vertritt, die er nicht einlösen kann, sondern gründet seinen Anspruch, experimentelle Beweise führen zu können, auf einer vorbildlichen Methodologie kausaler Erklärungen, was seine Kritiker allerdings übersehen. 2. Goethe ist kein Antiwissenschaftler, der einen einzigartigen Kontrapunkt zur vorherrschenden wissenschaftlichen Tradition bildet, sondern steht inmitten (...) traditioneller Auffassungen zur Farbenlehre, deren experimentelle und methodologische Grundlagen bezüglich eines Erklärungsanspruches denen Newtons unterlegen sind. (shrink)
Es wird anhand von Fallbeispielen aus der Geschichte der Farbenlehre inwissenschaftstheoretische Probleme eingeführt. Das Buch dient als Grundlagefür eine anwendungsbezogene Lehre und als Einführung in folgende ThemenbereicheNewton vs. Goethe; Theorie und Experiment, Colormetrie; Empfindungsmessung;Helmholtz vs. Hering; Theorienevaluation, Psychologische Farbenlehre; Phänomenologie,Farbausschluss; Beweistheorie, Farbdefinitionen; Theorien- und Begriffsbildung.Neben Aufgaben, Texten und Lösungsvorschlägen finden sich eine Bibliographiesowie Einleitungen zu den behandelten Fragen und Lösungsvorschlägen derjeweiligen Themen.
The young Wittgenstein called his conception of logic “New Logic” and opposed it to the “Old Logic”, i.e. Frege’s and Russell’s systems of logic. In this paper the basic objects of Wittgenstein’s conception of a New Logic are outlined in contrast to classical logic. The detailed elaboration of Wittgenstein’s conception depends on the realization of his ab-notation for first order logic.
This paper reveals two fallacies in Turing's undecidability proof of first-order logic (FOL), namely, (i) an 'extensional fallacy': from the fact that a sentence is an instance of a provable FOL formula, it is inferred that a meaningful sentence is proven, and (ii) a 'fallacy of substitution': from the fact that a sentence is an instance of a provable FOL formula, it is inferred that a true sentence is proven. The first fallacy erroneously suggests that Turing's proof of the non-existence (...) of a circle-free machine that decides whether an arbitrary machine is circular proves a significant proposition. The second fallacy suggests that FOL is undecidable. (shrink)
Das Buch vermittelt die Grundlagen der Aussagen- und erweiterten Prädikatenlogik in 12 Lektionen. Neben Techniken zum überprüfen der Schlüssigkeit von Argumenten bilden die Kunst des Formalisierens wissenschaftlicher Argumente und metalogische Fragen den Inhalt des Buches. Das Buch eignet sich in Verbindung mit begleitenden interaktiven Übungseinheiten und Klausuren, die ber Internet zugänglich sind, sowohl zum Selbststudium als auch für Einführungskurse in die Logik. Die zweite berarbeitete Auflage erscheint in einem größeren und besser lesbaren Format.
This paper compares several models of formalization. It articulates criteria of correct formalization and identifies their problems. All of the discussed criteria are so called “semantic” criteria, which refer to the interpretation of logical formulas. However, as will be shown, different versions of an implicitly applied or explicitly stated criterion of correctness depend on different understandings of “interpretation” in this context.
One of the central logical ideas in Wittgenstein's Tractatus logico-philosophicus is the elimination of the identity sign in favor of the so-called "exclusive interpretation" of names and quantifiers requiring different names to refer to different objects and different variables to take different values. In this paper, we examine a recent development of these ideas in papers by Kai Wehmeier. We diagnose two main problems of Wehmeier's account, the first concerning the treatment of individual constants, the second concerning so-called "pseudo-propositions" of (...) classical logic such as a=a or a=b v b=c -> a=c. We argue that overcoming these problems requires two fairly drastic departures from Wehmeier's account: Not every formula of classical first-order logic will be translatable into a single formula of Wittgenstein's exclusive notation. Instead, there will often be a multiplicity of possible translations, revealing the original "inclusive" formulas to be ambiguous. Certain formulas of first-order logic such as a=a will not be translatable into Wittgenstein's notation at all, being thereby revealed as nonsensical pseudo-propositions which should be excluded from a "correct" conceptual notation. We provide translation procedures from inclusive quantifier-free logic into the exclusive notation that take these modifications into account and define a notion of logical equivalence suitable for assessing these translations. (shrink)
This paper systematically outlines Wittgenstein's ab-notation. The purpose of this notation is to provide a proof procedure in which ordinary logical formulas are converted into ideal symbols that identify the logical properties of the initial formulas. The general ideas underlying this procedure are in opposition to a traditional conception of axiomatic proof and are related to Peirce's iconic logic. Based on Wittgenstein's scanty remarks concerning his ab-notation, which almost all apply to propositional logic, this paper explains how to extend his (...) method to a subset of first-order formulas, namely, formulas that do not contain dyadic sentential connectives within the scope of any quantifier. (shrink)