Biomedical subjects

Ruth M J Byrne

Publications and source records attributed to Ruth M J Byrne.

6 recordsLinked to original sources

PubMed2005

Counterfactual and semifactual conditionals prime alternative possibilities.

The authors examined in 3 experiments the comprehension of counterfactuals, such as "If it had rained, the plants would have bloomed," and semifactuals, such as "Even if it had rained, the plants would have bloomed," compared with indicative conditionals, "If it rained, the plants bloomed." The first experiment showed that people read the negative conjunction, "not p and not q" faster when it was primed by a counterfactual than when it was primed by an indicative conditional. They read the affirmative conjunction, "p and q" equally quickly when it was primed by either conditional. The 2nd experiment showed that people read the negated-antecedent conjunction, "not p and q" faster when it was primed by a semifactual conditional. The 3rd experiment corroborated these results in a direct comparison of counterfactuals and semifactuals. The authors discuss the implications of the results for the mental representations of different conditionals.

Cognition↗

PubMed2004

Counterfactual and prefactual conditionals.

We consider reasoning about prefactual possibilities in the future, for example, "if I were to win the lottery next year I would buy a yacht" and counterfactual possibilities, for example, "if I had won the lottery last year, I would have bought a yacht." People may reason about indicative conditionals, for example, "if I won the lottery I bought a yacht" by keeping in mind a few true possibilities, for example, "I won the lottery and I bought a yacht." They understand counterfactuals by keeping in mind two possibilities, the conjecture, "I won the lottery and I bought a yacht" and the presupposed facts, "I did not win the lottery and I did not buy a yacht." We report the results of three experiments on prefactuals that examine what people judge them to imply, the possibilities they judge to be consistent with them, and the inferences they judge to follow from them. The results show that reasoners keep a single possibility in mind to understand a prefactual.

Adolescent↗

PubMed2004

Counterfactual thinking: the temporal order effect.

People often think about how things might have happened differently. Their counterfactual thoughts tend to mentally undo the most recent event in an independent sequence. Consider a game in which two players must each pick the same color card, both red or both black. The first picks black and the second picks red and so they lose. People think, "If only the second player had picked black." Our study tested the idea that the ways in which the players could have won provide counterfactual alternatives to the facts. In three experiments, the same set of facts (both players picked black cards), and the same winning conditions (to win in this new game they must pick different color cards) were presented, but the description of the winning conditions varied (e.g., "if one or the other but not both picks a red card" vs. "if one or the other but not both picks a black card"). The results showed that the temporal order effect can be produced or reversed by different descriptions. The descriptions make accessible different elements of the winning possibilities. A theory of the mental representations and cognitive processes underlying counterfactual thinking in the temporal order effect is described.

Adolescent↗

PubMed2002

Conditionals: a theory of meaning, pragmatics, and inference.

The authors outline a theory of conditionals of the form If A then C and If A then possibly C. The 2 sorts of conditional have separate core meanings that refer to sets of possibilities. Knowledge, pragmatics, and semantics can modulate these meanings. Modulation can add information about temporal and other relations between antecedent and consequent. It can also prevent the construction of possibilities to yield 10 distinct sets of possibilities to which conditionals can refer. The mental representation of a conditional normally makes explicit only the possibilities in which its antecedent is true, yielding other possibilities implicitly. Reasoners tend to focus on the explicit possibilities. The theory predicts the major phenomena of understanding and reasoning with conditionals.

Humans↗

PubMed2002

Temporal and causal order effects in thinking about what might have been.

When people think counterfactually about what might have been different for a sequence of events, they are influenced by the order in which the events occurred. They tend to mentally undo the most recent event in a temporal sequence of two events. But they tend to mentally undo the first event in a causal sequence of four events. We report the results of two experiments that show that the temporal and causal order effects are not dependent on the number of events in the sequence. Our first experiment, with 300 participants, shows that the temporal order effect occurs for sequences with four events as well as for sequences with two events. Our second experiment, with 372 participants, shows that the causal order effect occurs for sequences with two events as well as for sequences with four events. We discuss the results in terms of the mental representations that people construct of temporal and causal sequences.

Humans↗

PubMed2002

Reasoning counterfactually: making inferences about things that didn't happen.

The authors investigated the relationship between reasoners' understanding of subjunctive conditionals (e.g., if p had happened, then q would have happened) and the inferences they were prepared to endorse. Reasoners who made a counterfactual interpretation of subjunctive statements (i.e., they judged the statement to imply that p and q did not happen) endorsed different inferences than those who did not. Those who made a counterfactual interpretation were more likely to (a) judge the situation in which p and q occurred to be inconsistent with the conditional statement and (b) make negative inferences such as modus tollens (i.e., approximately q therefore approximately p). These findings occurred with familiar and unfamiliar content, affirmative and negative conditionals, and conditional and biconditional relations.

Adolescent↗