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Sopholab Experimental Computational Philosophy SophoLab Experimental Computational Philosophy Proefschrift ter verkrijging van de graad van doctor aan de Technische Universiteit Delft, op gezag van de Rector Magnificus Prof.dr.ir. J.T. Fokkema voorzitter van het College voor Promoties, in het openbaar te verdedigen op maandag 7 mei 2007 om 12:30 uur door Vincent WIEGEL doctorandus in de economie doctorandus in de filosofie geboren te Rhenen 1 Dit proefschrift is goedgekeurd door de promotoren: Prof. dr. M.J. van den Hoven Dr.ir. J. van den Berg (toegevoegd promotor) Samenstelling promotiecommissie Rector Magnificus, voorzitter Prof. dr. M.J. van den Hoven, Technische Universiteit Delft, Promotor Dr. ir. J. van den Berg, Technische Universiteit Delft, Toegevoegd Promotor Prof. dr. J.P.M. Groenewegen, Technische Universiteit Delft Prof. dr. ir. P.A. Kroes, Technische Universiteit Delft Prof. dr. J.H. Moor, Dartmouth College, Hanover, USA Dr. L. Floridi, Universit‡ degli Studi di Bari, Italië University of Oxford, Engeland Dr. G.J.C. Lokhorst, Technische Universiteit Delft, Adviseur Dr. G.J.C. Lokhorst heeft als begeleider in belangrijke mate aan de totstandkoming van het proefschrift bijgedragen. ISBN: 978-90-5638-168-4 2 Voor W, M, en C, mijn medereizigers “Elk kompas dat ik in gedachten raadpleeg, voert me naar een denkbeeldig land. Ik ben voortdurend op zoek naar nieuwe ideeën en inzichten, ik zoek geen bevestiging van wat ik al weet.” De bespiegelingen van Fra Mauro, in ‘De droom van een kaartenmaker’. Fra Mauro was een monnik die leefde in de 15e eeuw, en werkte als cartograaf aan het hof van Venetië. “Every compass I consult in my mind, takes me to an imaginary land. I am constantly looking for new ideas and insights, I do not seek confirmation of what I already know.” Reflections of Fra Mauro, in ‘A mapmaker’s dream.’ Fra Mauro was a monk living in 15th century, working as a cartographer to the court of Venice. 3 Simon Stevin Series in the Philosophy of Technology Editors: Peter Kroes and Anthonie Meijers Volume 1: Marcel Scheele, The Proper Use of Artefacts: A philosophical theory of the social constitution of artefact functions Volume 2: Anke van Gorp, Ethical issues in engineering design: Safety and Sustainability Volume 3: Vincent Wiegel, SophoLab. Experimental Computational Philosophy © Vincent Wiegel, 2007 Alle rechten voorbehouden. Niets uit deze uitgave mag worden verveelvoudigd, opgeslagen in een geautomatiseerd gegevensbestand, of openbaar gemaakt, in enige vorm of op enige wijze, hetzij elektronisch, mechanisch, door fotokopieën, opnamen of enige andere manier, zonder voorafgaande schriftelijke toestemming van de uitgever. Citaten voor niet-commercieel gebruik kunnen wel zonder toestemming worden overgenomen. Wiegel, V. SophoLab. Experimental Computational Philosophy Champs Elyseesweg 24 6213 AA MAASTRICHT E: [email protected] ISBN: 978-90-5638-168-4 4 Contents - brief Contents - brief 5 Contents - detailed 7 Acknowledgements 11 1 Introduction 13 2 Methodological reflections on philosophy and experimentation 47 3 Morality for artificial agents: implementing negative moral commands 89 4 Deontic epistemic action logic: privacy & autonomous software agents 109 5 Voting: testing rule- and act-utilitarianism in an experimental setting 135 6 Conclusions 159 Literature 169 Epilogue 175 Nederlandse samenvatting 181 Index 187 5 Contents - detailed Contents - brief 5 Contents - detailed 7 Acknowledgements 11 1 Introduction 13 1.1 Daunting complexity 17 1.2 Combining four research areas 20 1.2.1 Moral philosophy 21 1.2.3 Modal logic 23 1.2.3 Agents, agents and agents 26 1.2.4 Computational philosophy 29 1.3 Recent research themes 31 1.3.1 Intelligent and moral agents 31 1.3.2 Moral responsibility and artificial agents 32 1.3.3 Rule-based ethics, connectionism, universalism, particularism 33 1.3.4 Experimentation in philosophy and social sciences 35 1.4 Organization of this thesis 41 1.4.1 Background 41 1.4.2 Hypotheses and research questions 43 1.4.3 Thesis lay-out 44 2 Methodological reflections on philosophy and experimentation 47 Abstract 47 2.1 Introduction 47 2.1.1 The role of the experiment 48 2.1.2 Reality, theory and computational model 52 2.1.3 The organization of this chapter 52 2.2 Methodology of philosophical experimentation 53 2.2.1 Research program and vision 53 2.2.2 Methodology 55 2.3 Thagard 58 2.4 Danielson 64 2.5 Some reflections 70 2.6 The methodology in detail 72 7 SophoLab - experimental computational philosophy 2.7 Intermediate conceptual framework 76 2.8 Methodological issues 79 2.8.1 Neutrality 80 2.8.2 Standards of philosophical experimentation 81 2.8.3 Functional equivalence 83 2.9 Evaluating theories 85 2.10 Conclusion 87 3 Morality for artificial agents: implementing negative moral commands 89 Abstract 89 3.1 Introduction 89 3.2 Implementation 90 3.3 Implementing negative moral commands 95 3.3.1. Belief 95 3.3.2. Desire 98 3.3.3. Intention 99 3.3.4. Pairwise combinations 100 3.4 Complex propositions ñ negative moral commands 102 3.5 Epistemology 106 3.6 Conclusion 107 4 Deontic epistemic action logic: privacy & autonomous software agents 109 Abstract 109 4.1 Problem description 109 4.2 Solution 111 4.3 Conceptual aspects 112 4.3.1 Triggers 112 4.3.2 Spheres 113 4.3.3 Information as an intentional agent 113 4.4 The implementation 115 4.4.1 Agent and Predicate/Data 116 4.4.2 Sphere 117 4.4.3 Beliefs 118 4.4.4 Triggers 119 4.3.5 Obligations 122 4.4.6 Role-rights matrix 124 4.4.7 Desire and intention 125 4.4.8 Illustration 126 4.5 Insurance and privacy 127 4.5.1 The test case 127 8 Contents 4.5.2 Results from the experiments 129 4.6 Conclusion 132 5 Voting: testing rule- and act-utilitarianism in an experimental setting 135 Abstract 135 5.1 Harsanyi’s theory of utilitarianism 136 5.2 Preparing the experiment 141 5.2.1 Step 1: decomposing 141 5.2.2 Steps 2 - 4: translating into framework 142 5.3 Modelling further 145 5.3.1 Steps 2 - 4 repeated: extending and adjusting 145 5.3.2 The SophoLab software framework 148 5.3.3 Step 5: Implementation ñ elements in the framework 148 5.4 Running the experiments 150 5.4.1 Steps 6 & 7 - Configuring and running the experiment 150 5.4.2 Decision rule and tolerance 153 5.4.3 Cost of information 153 5.4.4 Inclination 153 5.4.5 Step 8 - Translating back to the theory 154 5.4.6 Step 9 - Conclusions regarding the theory 154 5.5 Conclusion 156 6 Conclusion 159 6.1 Hypotheses, deliverables and questions 159 6.1.1 Methodology of experimental philosophy 161 6.1.2 Modelling and constructing experiments on moral philosophy 162 6.1.3 Running experiments 163 6.2 This research and its relevance: some news items 164 6.3 Future research 166 Literature 169 Epilogue 175 Drivers for SophoLab 175 Approach 176 Building blocks: modelling & implementation 177 Some results 179 Nederlandse samenvatting 181 Index 187 9 Acknowledgements One of the pleasures of writing a thesis and publishing it, is that you can share your joy with all those that helped you, and those that are dear to you. I will not list them all individually, but I do know how much I benefited from their help and support, and so do they. There a few people I would like thank explicitly. Some of my English colleagues and acquaintances have helped me with the spelling and grammar. Writing in a language that is not one’s own can be diffi- cult. I benefited greatly from various people, native and non-native speakers alike. In particular, I would like to thank Mr. C. Burgener and Mrs. Melissa Gilmore. Also greatly appreciated in this context are the comments from review- ers of the papers and of the thesis. Any errors left are of course mine1. Mr. A. van Berkum, director Flex at ING, kindly provided the money to buy the software I used in this research. A brave move as we had no clue what would come out of the experiments. My dear uncle Mr. M. Wiegel put me on the programming track that got me to this stage. Mrs. Henneke Filiz-Piekhaar, thanks for your support throughout the process and the procedures. I owe a big thank you to Dr. Jan van den Berg for all the effort that he put in when he became my ‘toegevoegd promotor’ at a fairly late stage. The discussions were always stimulating. Dr. Gert-Jan Lokhorst has helped me throughout the whole journey. He kept me in check when the scope was in danger of expanding to undo-able dimensions. Thank you, Gert-Jan! Most of all I owe to Prof. Jeroen van den Hoven, who was involved from the start as well. When I first told him about my ideas he sup- ported and encouraged me, and ultimately made it possible for me to write and defend the thesis at the Delft University of Technology. All but one chapter have been published either in journals or presented at conferences. It was a great pleasure to meet many researchers, and have the ability to present ideas to them. The chapters have been modified only slightly. The introductory and conclusion chapters are new. Chapter 2 is forthcoming in ETIN. Chapter 3 was presented at iC&P in Laval 2006 and will appear in the proceedings. Chapter 4 was presented at the CEPE 2005 conference and appeared in ETIN. Chapter 5 is currently under review. The Epilogue is based on an invited presentation that was given at the ALife X 2006 conference, and appeared in the proceedings.
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