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Signaling Games in Light of Later Wittgenstein José Pedro Faria E Vasconcelos Correia D 2019

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Signaling Games in Light of Later Wittgenstein José Pedro Faria E Vasconcelos Correia D 2019 Programa Doutoral em Filosofia Meaningful play: Signaling games in light of later Wittgenstein José Pedro Faria e Vasconcelos Correia D 2019 José Pedro Correia Meaningful play Signaling games in light of later Wittgenstein Tese realizada no âmbito do Programa Doutoral em Filosofia, orientada pelo Professor Doutor João Alberto Cardoso Gomes Pinto Faculdade de Letras da Universidade do Porto Setembro de 2019 Meaningful play Signaling games in light of later Wittgenstein José Pedro Correia Tese realizada no âmbito do Programa Doutoral em Filosofia, orientada pelo Professor Doutor João Alberto Cardoso Gomes Pinto Membros do Júri Presidente: Vogais: À minha mãe Contents Declaração de honra i Agradecimentos iii Resumo v Abstract vii List of Figures viii List of Tables ix Introduction 1 I Background 5 1 Reading the Philosophical Investigations 7 1.1 Varieties of interpretation . 8 1.2 Wittgenstein, the pragmatist? . 13 1.3 A reading of later Wittgenstein . 17 2 Signaling games 21 2.1 A short introduction . 22 2.2 Anatomy of a signaling game . 28 II Later Wittgenstein and signaling games 51 3 Room for systematicity 53 3.1 In pursuit of chimeras . 54 3.2 Explanations of meaning and philosophical method . 63 1 2 CONTENTS 3.3 The use of toy language-games as method . 73 3.4 Systematizing toy language-games . 78 4 An organic picture of language 89 4.1 Practice, heterogeneity, and dynamism . 89 4.2 Meaning and use . 95 4.3 Signaling games and the organic picture . 100 5 It’s not the word that counts 109 5.1 Everyday objects . 110 5.2 Simples . 115 5.3 Mental entities . 122 5.4 Correspondence in signaling games . 130 6 Rules and meaning 141 6.1 Misunderstanding rules . 143 6.2 An alternative picture . 153 6.3 Rules in signaling games . 158 Conclusions 171 A Towards an ecology of vagueness 177 A.1 Vagueness and rationality . 178 A.2 Signaling games . 181 A.3 Vagueness in sim-max games . 185 A.4 The ecology of vagueness . 190 A.5 Two multi-population models of imprecise imitation . 193 A.6 Conclusions . 205 Bibliography 207 Declaração de honra Declaro que a presente tese é de minha autoria e não foi utilizada previamente noutro curso ou unidade curricular, desta ou de outra instituição. As referências a outros autores (afirmações, ideias, pensamentos) respeitam escrupulosamente as re- gras da atribuição, e encontram-se devidamente indicadas no texto e nas referências bibliográficas, de acordo com as normas de referenciação. Tenho consciência de que a prática de plágio e auto-plágio constitui um ilícito académico. Porto, 30 de Setembro de 2019 José Pedro Correia i Agradecimentos Em primeiro lugar, gostaria de agradecer à professora Sofia Miguens, ao Mind, Language, and Action Group (MLAG), e ao Instituto de Filosofia (IF), por terem aceite acolher-me para levar a cabo este projeto. Agradeço também ao professor João Alberto Pinto por ter aceite orientar a minha tese e pelo apoio que deu durante a sua execução. Adicionalmente, estou imensamente agradecido à Fundação para a Ciência e Tecnologia pelo apoio financeiro (bolsa número SFRH/BD/100437/2014), sem o qual a elaboração deste trabalho não teria sido possível. I also thank Michael Franke for supporting my application to this PhD grant. Durante o período de desenvolvimento desta tese, beneficiei de discussões esti- mulantes (mesmo que não necessariamente ligadas aos tópicos aqui abordados) com outros membros do IF. Em particular, gostaria de agradecer aos professores respon- sáveis pelas cadeiras que frequentei no ano curricular, que com os tópicos lecionados e as conversas aí geradas ajudaram de uma maneira ou de outra a cristalizar algu- mas ideias contidas nesta tese, incluindo a professora Maria João Couto, a professora Sofia Miguens, o professor João Alberto Pinto, e o professor Paulo Tunhas. Estou adicionalmente grato ao MLAG por ter podido participar na organização de ati- vidades no contexto do grupo, o que enriqueceu a experiência, e em particular à Diana Couto com quem mais colaborei nessas iniciativas. Agradeço a todos os ou- tros membros do MLAG, e aos restantes participantes, com quem tive o prazer de trocar ideias no contexto dessas atividades. When it comes more directly to the con- tents of this thesis, I will always be indebted to Michael Franke and Elliott Wagner for introducing me to signaling games in a very inspiring way, and additionally to Michael for very fruitful collaborations since then, one of which is included in this thesis. I would also like to thank Jiwon Kim, not only for some highly stimulat- ing conversations about philosophy, but for also taking the time to review and give feedback on part of this thesis. Agradeço também a todos os amigos e amigas que em algum momento nestes quatro anos acompanharam este processo, não só em convívios e atividades para além do doutoramento, mas também tolerando os eventuais desabafos ou até esti- mulando as divagações filosóficas. Esquivo-me de mencionar nomes com receio de me esquecer de alguém, mas vocês sabem quem são. This goes also to my friends abroad. Thank you for your companionship and support during this journey. Final- mente, gostaria de agradecer aos meus pais por apoiarem este desvio de percurso, aparentemente pouco sábio, com a confiança que sempre demonstrarem em mim e nas minhas escolhas. iii Resumo Esta tese explora as ligações entre a filosofia tardia de Ludwig Wittgenstein e método de modelação dos jogos de sinalização (signaling games). Em particular, foco-me nas Investigações Filosóficas, nomeadamente em quatro tópicos aí desen- volvidos: as observações de Wittgenstein sobre filosofia e método, a sua imagem da linguagem como uma prática dinâmica e heterogénea, as suas críticas a algumas variantes da conceção do significado como uma forma de correspondência, e as suas discussões sobre o seguimento de regras. Defendo que o método dos jogos de sina- lização fornece-nos ferramentas que permitem um estudo do significado que está no geral bem alinhado com esses aspetos da filosofia tardia de Wittgenstein. Adicio- nalmente, a comparação revela trabalho na área dos jogos de sinalização que pode ser visto como filosoficamente problemático à luz dos comentários de Wittgenstein, e aponta para potenciais melhorias e direções para trabalho futuro. Palavras-chave: filosofia da linguagem, Wittgenstein, jogos de sinalização v Abstract This thesis explores the connections between Ludwig Wittgenstein’s later philos- ophy and the modeling framework of signaling games. In particular, I focus on the Philosophical Investigations and on four topics within it: Wittgenstein’s remarks on philosophy and method, his picture of language as a dynamic and heterogeneous practice, his criticism of some variants of conceptions of meaning as correspondence, and his discussions on rules and rule-following. I argue that the signaling games framework provides us tools that enable a study of meaning that is generally in line with these aspects of Wittgenstein’s later philosophy. Exploring the connec- tions additionally reveals where some work in the signaling games literature goes philosophically astray in light of Wittgenstein’s remarks, and points to ideas for improvements and future work. Keywords: philosophy of language, Wittgenstein, signaling games vii List of Figures 2.1 Examples of strategy profiles. 26 2.2 Simulation results of a binary signaling game under the one-population replicator dynamic. 29 3.1 Arrangement of colored squares from §48 and interpretation schemas. 66 4.1 Example of a random mixed strategy profile for a simple binary signaling game. 106 5.1 Example of how a mixed strategy profile can be merged. 139 6.1 Interpretation schemas for the builder’s language variant of §86. 146 A.1 Example strategies for a state space with 50 states. 186 A.2 Evolution of population proportions through time for each simulation trial of the tight interaction model. 197 A.3 Development of some metrics through time for the α = 0 population. 199 A.4 Evolution of population proportions through time for each simulation trial of the loose interaction model. 202 A.5 First iteration with convex sender strategies for each simulation trial of the loose interaction model. 203 A.6 Expected utilities for trial 88 of the loose interaction model. 204 viii List of Tables 1.1 Rough categorization of different interpretations of Wittgenstein’s metaphi- losophy and practice in the Philosophical Investigations. 12 2.1 Expected utility matrix. 25 2.2 Possible strategy profiles in a binary signaling game. 27 ix Introduction Language is a pervasive presence in the lives of human beings. So much so, that the ability to use language in the ways that we do is often considered one of the quintessential characteristics that differentiate us from other animals. Throughout the ages, many have attempted to develop a better understanding of how language works, from philosophers, to linguists, psychologists, anthropologists, neuroscien- tists, and researchers from many other fields. Despite language’s ubiquity in our practices, and the great deal of attention it has received, there can be a feeling that progress in developing the theoretical tools to understand it better has been extremely slow, especially when compared with the study of other phenomena in natural science. Although we have confidence in our growing knowledge of quarks and atoms, molecules and chemical reactions, genes and cell structure, planets and galaxies, and so many other things, we seem to struggle to provide a satisfying theoretical characterization of a sentence as simple as “Hello!” This is especially the case when it comes to the aspect of language that is the focus of this thesis: meaning. Efforts to get a better theoretical grip on meaning go back to philosophers in Ancient Greece, and have especially become an important part of philosophical practice since the so-called linguistic turn (Rorty, 1967).
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