Michael Messerli

In this paper, we confront two prevailing views of rationality—reason- and coherence-based theories—with empirical facts. While the experimental resolution of the debate between both theories is challenging, we examine two cases in which these theories make distinct predictions regarding whether an agent is deemed rational or not. By directly pitting reason-based against coherence-based theories, our findings indicate that reasons play a more influential role in shaping people's attributions of rationality than coherence.

For most of its history, decision theory has investigated the rational choices of humans under the assumption of static preferences. Human preferences, however, change. In recent years, decision theory has increasingly acknowledged the reality of preference change throughout life. This Element provides an accessible introduction and new contributions to the debates on preference change. It is divided into three chapters. In the first chapter, the authors discuss what preference change is and whether we can integrate it into decision theory. In the second chapter, they present models of preference change, including a novel proposal of their own. In the third and final chapter, they discuss how we can rationally choose a course of action when our preferences might change. Both the transformative experience literature and recent work on choosing for changing selves are discussed.

Some decisions we make—such as becoming a parent or moving to a different part of the world—are transformative. According to L. A. Paul, transformative decisions pose a major problem to us because they fall outside the realm of rationality. Her argument for that conclusion rests on the premise that subjective value is central in transformative decisions. This paper challenges that premise and hence the overall conclusion that transformative decisions usually are not rational. In the theoretical part of the paper, we specify conditions under which transformative decisions are possibly rational and likely rational. The data we present in the empirical part of the paper reveal that subjective value often plays only a minor role in people’s decision-making process. Putting both parts together, we argue that people have a great chance of making rational transformative choices.

In hard cases of comparison, people are faced with two options neither of which is conceived of as better, worse, or equally good compared to the other. Most philosophers claim that hard cases can indeed be distinguished from cases in which two options are equally good, and can be characterized by a failure of transitive reasoning. It is a much more controversial matter and at the heart of an ongoing debate, whether the options in hard cases of comparison should be interpreted as incomparable, on par, or roughly equal. So far, however, none of these claims and interpretations have been tested. This paper presents the first empirical investigation on hard cases, intransitive reasoning, and incomparability. Our results reveal that hard cases present real-world dilemmas in which a significant majority of people violate transitivity. After suggesting a way of operationalizing the notion of incomparability, we provide empirical evidence that the options in some hard cases are not considered to be incomparable. Theories of rough equality or parity seem to provide better interpretations of our results.

Weakness of the will remains a perplexing issue. Though philosophers have made substantial progress in homing in on what counts as a weak will, there is little agreement on whether weakness of the will is irrational, and if so, why. In this paper, we take an empirical approach towards the rationality of weakness of the will. After introducing the philosophical debate, we present the results of an empirical study that reveals that people take a “dual sensitivity”, as we shall put it, towards assessing the rationality of weak-willed behavior. Put succinctly, intending X against your value judgements is assessed irrational; yet, in the same situation, intending X is assessed significantly less irrational if you judge X as something you ought to do. After discussing this result, we turn to the question of whether there is a plausible theory of rationality than can account for the dual sensitivity of the rationality assessments. We show that a success-based account can make sense of the dual sensitivity our empirical results reveal.

Affect-based theorists and life satisfaction theorists disagree about the nature of happiness, but agree about this methodological principle: a philosophical theory of happiness should be in line with the folk concept HAPPINESS. In this article, we present two empirical studies indicating that it is affect-based theories that get the folk concept HAPPINESS right: competent speakers judge a person to be happy if and only if that person is described as feeling pleasure/good most of the time. Our studies also show that the judgement that a person is feeling pleasure/good most of the time reliably brings about the judgement that they are satisfied with their life, even if that person is described as not satisfied. We suggest that this direct causal relation between the concepts POSITIVE AFFECT and LIFE SATISFACTION might explain why many philosophers have been attracted to life satisfaction theories.

In the last seven years, philosophers have discussed the topic of transformative experiences. In this paper, we contribute to a crucial issue that is currently under-researched: transformative experiences' influence on cognitive modelling. We argue that cognitive modelling can be operationalized as affective forecasting, and we compare transformative and non-transformative experiences with respect to the ability of affective forecasting. Our finding is that decision-makers’ performance in cognitively modelling transformative experiences does not systematically differ from decision-makers’ performance in cognitively modelling non-transformative experiences. This claim stands in strict opposition to L.A. Paul’s main argument.

People are often faced with so called hard choices – also known as hard cases of comparison. In trying to characterize these hard choices, philosophers have made two central claims. First, failure of transitivity underlies hard cases of comparison. Second, using a random procedure is considered inappropriate in order to arrive at a decision in hard cases. While having some argumentative support, both claims primarily rely on expert intuitions. The results of the experiments we present in this paper challenge both claims, as well as the representativeness of expert intuitions that support these claims, by showing that most people violate transitivity only if a hard choice is important, and find it appropriate to use a random procedure even in hard cases of comparison.