MOTIVATION MATTERS: A CRITICAL ANALYSIS AND REFUTATION OF EVOLUTIONARY ARGUMENTS FOR PSYCHOLOGICAL ALTRUISM Fred Curry A Dissertation Submitted to the Graduate College of Bowling Green State University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY May 2007 Committee: Michael Bradie, Advisor Thomas Wymer Graduate Faculty Representative David Sobel Sarah Worley © 2007 Fredrick Curry All Rights Reserved iii ABSTRACT Dr. Michael Bradie, Advisor The origin of altruistic behavior has long been a puzzle for evolutionary biologists, beginning with Darwin. Although group selection was first favored to explain cooperative and altruistic behaviors, the forces of individual selection came to be seen as far more prevalent, powerful, and responsive to change. The theory of group selection was replaced by other explanations for altruistic behavior such as kin selection (inclusive fitness theory) and game theory. Recently, however, group selection has been regaining credibility in evolutionary biology. This resurgence is largely due to the work of two of the most prominent proponents of group selection David Sloan Wilson, a biologist, and Eliot Sober, a philosopher of science, who believe evolutionary arguments not only explain the origin of altruistic behaviors but also help resolve the psychological egoism versus altruism debate by providing evidence that natural selection favors altruistic motivations (psychological altruism). While there is no necessary link between the existence of group selection and altruistic motivation, if Sober and Wilson are right that group selection pressures are nearly ubiquitous for social organisms, this additional selection pressure would mean that cooperative strategies, including true altruism, would be beneficial more often than under a scenario that only includes selection at the individual level. Their argument rests on two evolutionary principles: the direct/indirect asymmetry principle, which posits a mechanism that triggers a fitness-enhancing response by directly detecting a fitness-relevant situation, and the two are better than one argument, which posits that an organism that has multiple mechanisms that serve the same function has a fitness advantage over an organism that has only one of these mechanisms. iv While both of these principles are valid, the evolutionary arguments that incorporate them are flawed and the evolutionary arguments arising from them should instead lead to the conclusion that psychological altruism is improbable. Psychological hedonism is a more likely trigger for the most fitness-enhancing degree of behavioral altruism had the chance to become firmly entrenched before psychological altruism could have ever even made an appearance. v To my late mother who would have been proud. vi ACKNOWLEDGMENTS I would like to give a special thanks to the following people: Dr. Michael Bradie, Dr. David Sobel, and Dr. Sara Worley who were always willing to share their valuable time and opinions with me. I am especially grateful to Dr. Bradie who petitioned the school for extra funding when my eye disease set my work back a year. My father Fred Curry senior, my brother Daniel Curry, and my grandmother Alberta Curry also very much deserve my gratitude for their emotional and, on occasion, financial support. I would also like to thank Jill Olthouse, who was a bottomless fount of emotional support and encouragement when times got tough. Finally I would be remiss if I didn‘t also thank that fine drug caffeine and all the late night pizza delivery persons of Bowling Green Ohio. vii TABLE OF CONTENTS TABLE OF CONTENTS ................................................................................................................ ii LIST OF FIGURES ..................................................................................................................... xiii MOTIVATION MATTERS: A CRITICAL ANALYSIS AND REFUTATION OF EVOLUTIONARY ARGUMENTS FOR PSYCHOLOGICAL ALTRUISM................... 1 Overview ..................................................................................................................................... 1 CHAPTER I: THE PSYCHOLOGICAL EGOISM VS. ALTRUISM DEBATE AND HISTORICAL ATTEMPTS TO RESOLVE IT ................................................................. 4 1_1 The Philosophical Arguments Concerning Psychological Egoism/Altruism ...................... 7 1_1.1 The Butler‘s Stone Argument against Hedonism ............................................................. 8 1_1.2 The Paradox of Hedonism .......................................................................................... 18 1_1.3 Nozick‘s Experience Machine .................................................................................... 21 1_1.3.1 The real reason why the experience machine argument fails. ............................. 29 1_2 The State of the Egoism/Altruism Debate in Light of Empirical Psychological Studies .................................................................................. 35 1_2.1 Problems Concerning Introspection ............................................................................ 36 1_2.2 Why the Law of Effect Fails as a Solution ................................................................. 38 1_2.3 Batson‘s Experiments ................................................................................................. 42 1_2.3.1 The Aversive-Arousal Reduction Hypothesis ..................................................... 44 1_2.3.2 The Empathy Specific Punishment Hypothesis ................................................... 48 1_2.3.3 The Empathy Specific Reward Hypothesis ......................................................... 50 1_2.3.4 ESR2: The Negative-State Relief Hypothesis ..................................................... 53 1_2.3.4 Batson Tests the Negative-State Relief Hypothesis (ESR2) ................................ 57 viii 1_2.3. 5 Batson and the Empathetic Joy Hypothesis ........................................................ 61 1_2.3.6 Some Conclusions Regarding Batson‘s Work ..................................................... 68 1_3 Summary ............................................................................................................................ 72 CHAPTER II: EVOLUTIONARY ALTRUISM AND GROUP SELECTION: HOW NATURAL SELECTION CAN FAVOR INDIVIDUAL SACRIFICE ................ 75 2_1 Two Different Concepts of Fitness .................................................................................... 81 2_2 Sober and Wilson‘s Definition of Evolutionary Altruism ................................................. 84 2_3 Group Selection and the Haystack Model ......................................................................... 87 2_4 Why Have Modern Biologists Been so Unreceptive to Group Selection? ........................ 94 2_5 Trait Groups and the Haystack Model without Haystacks ................................................ 99 2_5.1 More Ways in Which Trait Groups Improve the Case for Group Selection ........................................................................................ 108 2_6 Real World Examples of Group Level Selection: ........................................................... 109 2_6.2 Artificial Group Selection for Egg Production ......................................................... 110 2_6.2 Examples of Group Selection Outside of the Lab..................................................... 111 2_7 How Have Biologists Explained Away Apparently Obvious Instances of Altruism and Cooperation in the Natural World? ....................................................... 115 2_7.1 Kin Selection ............................................................................................................. 115 2_7.2 Evolutionary Game Theory and Reciprocal Altruism .............................................. 119 2_8 Applying Sober and Wilson‘s Multi Level Selection Theory to Real Populations ......................................................................................................... 129 2_9 Summary .......................................................................................................................... 134 CHAPTER III: ADAPTATIONS THAT ENHANCE GROUP SELECTION .......................... 136 ix 3_1 Assortative Behavior ........................................................................................................ 137 3_1.1 Wilson and Dugatkin‘s Simulations and the Power of Assortative Behavior ............................................................................... 143 3_1.1.1 The problem of origination. ............................................................................... 147 3_1.1.2 What do guppies have to do with human beings?.............................................. 150 3_1.2 Recap ......................................................................................................................... 153 3_2 Carrots, Sticks, and Altruism ........................................................................................... 154 3_2.1 Another Look at the Guppies .................................................................................... 158 3_2.2 How Punishment Amplifies Altruism ....................................................................... 160 3_2.2.1 Does Punishment Reduce Instances of True Altruism? ..................................... 163 3_2.3 Another Kind of Freeloader .....................................................................................