THE CAPGRAS DELUSION AN INTEGRATED APPROACH Neralie Diane Wise BA (Hon) Philosophy Macquarie University NSW Australia This thesis is presented for the degree of Doctor of Philosophy submitted in the Philosophy Department, Faculty of Arts Macquarie University August 2012 Table of Contents TABLE OF CONTENTS .....................................................................................................................II TABLE OF FIGURES ....................................................................................................................... VI ABSTRACT ....................................................................................................................................... VII STATEMENT OF CANDIDATE .................................................................................................. VIII ACKNOWLEDGEMENTS ............................................................................................................... IX INTRODUCTION ............................................................................................................................... 1 1. Introduction ................................................................................................................................................ 1 2. Thesis structure ......................................................................................................................................... 5 3. Part One ........................................................................................................................................................ 6 4. Part Two .................................................................................................................................................... 13 PART ONE ........................................................................................................................................ 20 CHAPTER 1: PHENOMENOLOGY AND DELUSIONS ........................................................... 21 1. Introduction ............................................................................................................................................. 21 SECTION ONE: KARL JASPERS.................................................................................................................... 21 1. Introduction ............................................................................................................................................. 21 2. Concepts ..................................................................................................................................................... 22 i) The psyche ............................................................................................................................................................................. 22 ii) Understanding.................................................................................................................................................................... 24 iii) Form and content ............................................................................................................................................................ 25 iv) The issue of reality .......................................................................................................................................................... 26 3. Delusions ................................................................................................................................................... 27 4. Conclusion ................................................................................................................................................. 30 SECTION TWO: FOLLOWING JASPERS ....................................................................................................... 31 1. Introduction ............................................................................................................................................. 31 2. Louis Sass .................................................................................................................................................. 32 i) Hyperreflexivity .................................................................................................................................................................. 33 ii) Body alienation .................................................................................................................................................................. 34 iii) Un-worlding ....................................................................................................................................................................... 34 iv) Subjectivization ................................................................................................................................................................ 35 3. Shaun Gallagher..................................................................................................................................... 37 i) Embodied and embedded cognition ......................................................................................................................... 38 ii) How the Body Shapes the Mind ................................................................................................................................. 39 iii) The multiple realities hypothesis ............................................................................................................................ 42 4. Conclusion ................................................................................................................................................. 45 CHAPTER 2: BRENDAN MAHER .............................................................................................. 47 1. Introduction ............................................................................................................................................. 47 SECTION ONE: BRENDAN MAHER ............................................................................................................ 47 1. Maher’s Challenge to Jaspers ........................................................................................................... 47 2. Maher’s Arguments............................................................................................................................... 49 i) The anomalous experience............................................................................................................................................ 49 ii) The question of rationality ........................................................................................................................................... 50 iii) Evolution and cognition ............................................................................................................................................... 51 iv) Impaired reasoning ........................................................................................................................................................ 52 3. Criticisms and Responses ................................................................................................................... 52 i) Why do most people fail to develop delusions when faced with anomalous experiences? ........... 52 ii) How does the model account for delusions that occur in the absence of any anomalous experience? ................................................................................................................................................................................ 53 iii) Why do patients develop a delusional explanation rather than a normal one? ............................... 54 iv) Why do patients, unlike normal people, fail to reject the explanation? ................................................ 54 4. Summary and Conclusion .................................................................................................................. 55 SECTION TWO: TESTING MAHER’S TWO CLAIMS .................................................................................. 55 ii 1. Introduction ............................................................................................................................................. 56 2. Biological Causes of Delusion .......................................................................................................... 56 i) Stroke, tumour, trauma, dementing illness and disease ................................................................................. 56 ii) Neuroimaging ..................................................................................................................................................................... 57 3. The Patient’s Thinking is Normal ................................................................................................... 58 i) Attributional style .............................................................................................................................................................. 59 ii) Conservation and observational adequacy .......................................................................................................... 60 iii) Probabilistic reasoning bias ....................................................................................................................................... 61 4. Summary and Conclusion .................................................................................................................