At the Intersection of Moral Psychology and Belief Formation: An Investigation of Bias, Biasing Influences and Behavioural Correlates Benjamin Michael Tappin Submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in the Department of Psychology Royal Holloway, University of London 2018 THE INTERSECTION OF MORAL PSYCHOLOGY & BELIEF FORMATION 2 Abstract This thesis presents an empirical investigation at the intersection of human moral psychology— people’s perceptions of good and bad, right and wrong—and human belief formation—how people evaluate evidence and update their beliefs. The investigation is divided into two parts. In Part I, across 6 studies I investigate (i) people’s beliefs about their own moral goodness relative to the average person—in particular, I ask whether and to what extent such beliefs are irrational—and (ii) people’s beliefs about the moral goodness of their political in-party relative to their political out-party. Using economic games, I subsequently test whether people’s beliefs regarding (i) and (ii) correlate with behavioural outcomes. Finally, I test whether people’s motivation to “do the morally right thing” underpins their prosocial behaviour. In Part II, also comprising 6 studies, I investigate several factors that are purported to influence belief formation in the morally-charged context of contemporary US politics. In particular, I study (i) whether belief updating is biased by the beliefs people already hold or by their desired political outcomes (or both), and (ii) the extent to which cognitive sophistication facilitates biased information processing such that people who are more sophisticated are more likely to form factual beliefs that are favourable to their political identities. I draw four main conclusions from my investigation. First, people’s beliefs about their own (vs. others') moral goodness, and about the moral goodness of their political in-party (vs. out-party), suggest a robust perception of “moral superiority”. Second, said perceptions of moral superiority are not reliably related to the behavioural outcomes I examine; more reliably related to these behavioural outcomes is people’s motivation to do what they perceive to be morally “right”. Third, belief formation is possibly biased by people’s desired outcomes and by their political identities, but the evidence is relatively undiagnostic on this front. The evidence is similarly undiagnostic as to whether cognitive sophistication facilitates such a bias. Fourth, and finally, following other scholars I conclude that reasonable inferences of “bias” in human belief formation demand evidence of systematic deviation from well-specified normative standards. THE INTERSECTION OF MORAL PSYCHOLOGY & BELIEF FORMATION 3 Acknowledgments There are numerous people to whom I owe a debt of gratitude for guiding and supporting me during the past three years of work. First and foremost, I am grateful to my supervisor, Ryan. I feel very fortunate to have had such a positive supervisory experience: Ryan walked the line admirably between giving me the creative and intellectual freedom to explore ideas and develop my own lines of work, whilst also being passionate and engaged when we discussed research ideas and designs together. He was open to the idea that psychological science required changes in practice to create a more rigorous research culture and reproducible literature—and he supported me wholeheartedly in exploring preregistration and other such practices during the early stages of my PhD studies. Perhaps most importantly, though, Ryan came to be a valued and trusted confidant and friend; a friendship that (for my part) will continue long into the future. The PhD experience would have been considerably less enjoyable were it not for the raucous scallywags for officemates that I had the fortune of befriending over the years. Together, we shared the ups and the downs (such as they are) of doctoral life; rendering the ups altogether more pleasurable, and the downs more bearable. Similar gratitude also goes to other colleagues and friends that I met along the way; including Robert Ross, Gary Lewis, Leslie van der Leer, Valerio Capraro, David Rand and Gordon Pennycook. Rob and Gary came to be good friends with whom I could chat about and discuss any topic, and be sure to receive cool and analytic insight. This was extremely helpful given that the topics of my thesis—moral psychology and politics—do not always lend themselves to reasonable or cool-headed discussion. I had the pleasure of meeting Leslie, Valerio, Dave and Gord during different stages of my studies, and we developed friendships and collaborations; some of which appear in this thesis, and others which are ongoing. Lastly, I would like to extend a special thanks to the three most important people in my life: my parents, and my partner—and partner-in-crime (!)—Leysa Forrest. I owe my mum, Janet Hooper, and my Dad, Alan Tappin, more than I can put into words. Suffice to say that I could not have wished for better support or for more opportunities in life than they have given to me. The work in this thesis is as much theirs as it is mine. I feel tremendously lucky to have met my partner, Leysa, in the early stages of my doctoral studies. She has been a source of relentless THE INTERSECTION OF MORAL PSYCHOLOGY & BELIEF FORMATION 4 love and support throughout the PhD, and I am forever grateful to her for putting up with the long working hours, the spells of self-doubt and questioning, and the other baggage that comes with PhD life. She has been my rock. THE INTERSECTION OF MORAL PSYCHOLOGY & BELIEF FORMATION 5 Table of Contents Bibliography of Work Completed During PhD ................................................... 7 Introduction .......................................................................................................... 8 Context of and Rationale for Research................................................................................................8 Meta Context ...................................................................................................................................8 Theoretical Context and Rationale ..................................................................................................9 Methodology ...................................................................................................... 15 Sampling Population and Strategy ....................................................................................................15 Measuring Outcomes: Self-Report and Behavioural Economic Games ...........................................21 Observational and Experimental Research Designs ..........................................................................24 Preregistration ...................................................................................................................................25 Part I: Perceived Moral Superiority and Moral Behaviour ................................ 26 Preface ...............................................................................................................................................26 1.1. The Illusion of Moral Superiority ..............................................................................................28 Abstract .........................................................................................................................................28 Introduction ...................................................................................................................................29 Methods .........................................................................................................................................32 Results ...........................................................................................................................................35 Discussion .....................................................................................................................................44 Supplemental Material ..................................................................................................................47 1.2. Investigating the Relationship between Self-Perceived Moral Superiority and Moral Behaviour Using Economic Games ....................................................................................................................49 Abstract .........................................................................................................................................49 Introduction ...................................................................................................................................50 Methods .........................................................................................................................................52 Results ...........................................................................................................................................57 Discussion .....................................................................................................................................63 Supplemental Material ..................................................................................................................67 1.3. Moral Polarization and Out-Party Hate in the US Political Context ..........................................75 Abstract .........................................................................................................................................75