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K I Manktelow

Publications and source records attributed to K I Manktelow.

5 recordsLinked to original sources

Conditions for the acceptance of deontic conditionals.

Recent psychological research has investigated how people assess the probability of an indicative conditional. Most people give the conditional probability of q given p as the probability of if p then q. Asking about the probability of an indicative conditional, one is in effect asking about its acceptability. But on what basis are deontic conditionals judged to be acceptable or unacceptable? Using a decision theoretic analysis, we argue that a deontic conditional, of the form if p then must q or if p then may q, will be judged acceptable to the extent that the p & q possibility is preferred to the p & not-q possibility. Two experiments are reported in which this prediction was upheld. There was also evidence that the pragmatic suitability of permission rules is partly determined by evaluations of the not-p & q possibility. Implications of these results for theories of deontic reasoning are discussed.

Adolescent↗

Causal and conditional inferences: a comment on Cummins (1995)

Cummins (1995) offers an analysis of causal and truth-functional sufficiency and necessity to predict and explain the effects on conditional inferences of two pragmatic factors: alternative causes and disabling conditions. However, the justification of these predictions is inconsistent. This note offers a modified analysis which puts her predictions on a sounder base: it is proposed that alternative causes and disabling conditions affect judgments of argument validity under three different models for the causal conditional.

Causality↗

Social roles and utilities in reasoning with deontic conditionals.

A set of experiments is reported in which a new formulation of deontic thinking is tested. This is that people represent subjective utilities inherent in conforming to or violating deontic statements, along with the social dynamics of these statements. The experiments used Wason's selection task and tested people's understanding of conditional permission. In the first two experiments, familiar scenarios referring to family interactions were used. In the third, an imaginary business content was used. In both cases it was apparent that people's thinking depended on their representation of the utilities associated with the agent of a permission statement (the party who lays down the rule) and the actor (the party whose behaviour is its target). The results are discussed as favouring an explanation in terms of mental models, rather than the schema theories which have dominated this field hitherto.

Cognition↗

Reasoning, decision making and rationality.

It is argued that reasoning in the real world supports decision making and is aimed at the achievement of goals. A distinction is developed between two notions of rationality: rationality which is reasoning in such a way as to achieve one's goals--within cognitive constraints--and rationality which is reasoning by a process of logic. This dichotomy is related to the philosophical distinction between practical and theoretical reasoning. It is argued that logicality (rationality) does not provide a good basis for rationality and some psychological research on deductive reasoning is re-examined in this light. First, we review belief bias effects in syllogistic reasoning, and argue that the phenomena do not support the interpretations of irrationality that are often placed upon them. Second, we review and discuss recent studies of deontic reasoning in the Wason selection task, which demonstrate the decision making, and rational nature of reasoning in realistic contexts. The final section of the paper examines contemporary decision theory and shows how it fails, in comparable manner to formal logic, to provide an adequate model for assessing the rationality of human reasoning and decision making.

Cognition↗