33 research outputs found
Relevance and Conditionals: A Synopsis of Open Pragmatic and Semantic Issues
Recently several papers have reported relevance effects on the cognitive assessments of indicative conditionals, which pose an explanatory challenge to the Suppositional Theory of conditionals advanced by David Over, which is influential in the psychology of reasoning. Some of these results concern the āEquationā (P(if A, then C) = P(C|A)), others the de Finetti truth table, and yet others the uncertain and-to-inference task. The purpose of this chapter is to take a Birdseye view on the debate and investigate some of the open theoretical issues posed by the empirical results. Central among these is whether to count these effects as belonging to pragmatics or semantics
Putting Inferentialism and the Suppositional Theory of Conditionals to the Test
This dissertation is devoted to empirically contrasting the Suppositional Theory of conditionals, which holds that indicative conditionals serve the purpose of engaging in hypothetical thought, and Inferentialism, which holds that indicative conditionals express reason relations. Throughout a series of experiments, probabilistic and truth-conditional variants of Inferentialism are investigated using new stimulus materials, which manipulate previously overlooked relevance conditions. These studies are some of the first published studies to directly investigate the central claims of Inferentialism empirically.
In contrast, the Suppositional Theory of conditionals has an impressive track record through more than a decade of intensive testing. The evidence for the Suppositional Theory encompasses three sources. Firstly, direct investigations of the probability of indicative conditionals, which substantiate āthe Equationā (P(if A, then C) = P(C|A)). Secondly, the pattern of results known as āthe defective truth tableā effect, which corroborates the de Finetti truth table. And thirdly, indirect evidence from the uncertain and-to-if inference task.
Through four studies each of these sources of evidence are scrutinized anew under the application of novel stimulus materials that factorially combine all permutations of prior and relevance levels of two conjoined sentences. The results indicate that the Equation only holds under positive relevance (P(C|A) ā P(C|Ā¬A) \u3e 0) for indicative conditionals. In the case of irrelevance (P(C|A) ā P(C|Ā¬A) = 0), or negative relevance (P(C|A) ā P(C|Ā¬A) \u3c 0), the strong relationship between P(if A, then C) and P(C|A) is disrupted. This finding suggests that participants tend to view natural language conditionals as defective under irrelevance and negative relevance (Chapter 2). Furthermore, most of the participants turn out only to be probabilistically coherent
above chance levels for the uncertain and-to-if inference in the positive relevance condition, when applying the Equation (Chapter 3). Finally, the results on the truth table task indicate that the de Finetti truth table is at most descriptive for about a third of the participants (Chapter 4).
Conversely, strong evidence for a probabilistic implementation of Inferentialism could be obtained from assessments of P(if A, then C) across relevance levels (Chapter 2) and the participantsā performance on the uncertain-and-to-if inference task (Chapter 3). Yet the results from the truth table task suggest that these findings could not be extended to truth-conditional Inferentialism (Chapter 4). On the contrary, strong dissociations could be found between the presence of an effect of the reason relation reading on the probability and acceptability evaluations of indicative conditionals (and connate sentences), and the lack of an effect of the reason relation reading on the truth evaluation of the same sentences. A birdās eye view on these surprising results is taken in the final chapter and it is discussed which perspectives these results open up for future research
Making Ranking Theory Useful for Psychology of Reasoning
An organizing theme of the dissertation is the issue of how to make philosophical theories useful for scientific purposes. An argument for the contention is presented that it doesnāt suffice merely to theoretically motivate oneās theories, and make them compatible with existing data, but that philosophers having this aim should ideally contribute to identifying unique and hard to vary predictions of their theories.
This methodological recommendation is applied to the ranking-theoretic approach to conditionals, which emphasizes the epistemic relevance and the expression of reason relations as part of the semantics of the natural language conditional. As a first step, this approach is theoretically motivated in a comparative discussion of other alternatives in psychology of reasoning, like the suppositional theory of conditionals, and novel approaches to the problems of compositionality and accounting for the objective purport of indicative conditionals are presented.
In a second step, a formal model is formulated, which allows us to derive quantitative predictions from the ranking-theoretic approach, and it is investigated which novel avenues of empirical research that this model opens up for.
Finally, a treatment is given of the problem of logical omniscience as it concerns the issue of whether ranking theory (and other similar approaches) makes too idealized assumptions about rationality to allow for interesting applications in psychology of reasoning. Building on the work of Robert Brandom, a novel solution to this problem is presented, which both opens up for new perspectives in psychology of reasoning and appears to be capable of satisfying a range of constraints on bridge principles between logic and norms of reasoning, which would otherwise stand in a tension
Relevance differently affects the truth, acceptability, and probability evaluations of āandā, ābutā, āthereforeā, and āifāthenā
In this study we investigate the influence of reason-relation readings of indicative conditionals and āandā/ābutā/āthereforeā sentences on various cognitive assessments. According to the Frege-Grice tradition, a dissociation is expected. Specifically, differences in the reason-relation reading of these sentences should affect participantsā evaluations of their acceptability but not of their truth value. In two experiments we tested this assumption by introducing a relevance manipulation into the truth-table task as well as in other tasks assessing the participantsā acceptability and probability evaluations. Across the two experiments a strong dissociation was found. The reason-relation reading of all four sentences strongly affected their probability and acceptability evaluations, but hardly affected their respective truth evaluations. Implications of this result for recent work on indicative conditionals are discussed
Reasoning Studies. From Single Norms to Individual Differences.
In review. Submitted for habilitation in psychology
Motivating the Relevance Approach to Conditionals
The aim is to theoretically motivate a relevance approach to (indicative) conditionals in a comparative discussion of the main alternatives. In particular, it will be argued that a relevance approach to conditionals is better motivated than the suppositional theory currently enjoying wide endorsement. In the course of this discussion, an argument will be presented of why failures of the epistemic relevance of the antecedent for the consequent should be counted as genuine semantic defects (as opposed to be relegated to pragmatics). Furthermore, strategies for dealing with compositionality and the perceived objective purport of indicative conditionals will be put forward
Conditionals, Individual Variation, and the Scorekeeping Task
In this manuscript we study individual variation in the
interpretation of conditionals by establishing individual
profiles of the participants based on their behavioral responses
and reflective attitudes. To investigate the participantsā
reflective attitudes we introduce a new experimental paradigm
called the Scorekeeping Task, and a Bayesian mixture model
tailored to analyze the data. The goal is thereby to identify the
participants who follow the Suppositional Theory of conditionals
and Inferentialism and to investigate their performance
on the uncertain and-to-if inference task