La deducción con condicionales en niños y adultosSupresión de inferencias, contrafactualidad y uso de la información epistémica

Zusammenfassung

Deductive ability holds an important place in academic performance, being part of the broad set of essential skills for school learning. However, the scarce volume of research on it contrasts with that devoted to other cognitive processes. This doctoral thesis focuses on deductive ability with conditionals and, in particular, with counterfactual conditionals. The general objectives of this thesis try to cover different aspects. On the one hand, we examine the role of some factors in the suppression of inferences, as well as whether there is an "additive" effect when several of them are used. On the other hand, we focus on reasoning with counterfactual conditionals, trying to analyse possible factors responsible for the limitations found in this kind of reasoning by children. Finally, we investigated how adults and children construct the counterfactual possibility and whether this depends on the developmental nature of the construction of negation. This thesis consists of five chapters. The first chapter introduces the most relevant aspects of the subject, including key concepts and terminology, as well as some of the most relevant studies. Chapter two contains a study with two experiments in which the effect of different factors on the suppression of inferences is analysed, as well as the possible additive effect of the use of several of them. To carry out the study, both experiments were designed with E-Prime. In them, participants had to perform the four basic inferences (MP, MT, AC and DA) after being presented with different information (only the conditional -‘if she runs, she is thirsty’-, additional information to the conditional -‘we know that she did not run, but was thirsty’- or after generating counterexamples -‘she could have eaten salt, it was very hot, etc.’-) The results confirm the suppression effect of the three factors studied. They also support an "additive " suppression effect when several factors are used. In chapter three we evaluate the ability to reason with counterfactuals in adults and children, examining possible factors causing the difficulty that, especially the youngest children, show when reasoning with this kind of conditionals. More specifically, we analyse the role of epistemic status (distinguishing the real and the hypothetical situation) and the grammatical component. For this purpose, we designed a task with a total of 8 stories, manipulating the grammatical component ("if there were..." vs. "even if there were...") that were read by the examiner. After each of them, two questions were asked: one related to making an inference from the counterfactual and the other related to the epistemic status of the counterfactual. The most relevant results support the developmental character, not only of counterfactual reasoning, but also of the ability to keep in mind mental labels and to distinguish real from hypothetical situations. In addition, they confirm the particular difficulty that children show in the latter ability. Likewise, the results suggest that the use of the concessive "even if" facilitates inferential response in both adults and children. Chapter four, as the previous one, consists of a study with two experiments. These focus on studying how both adults (experiment 1) and children (experiment 2) construct the counterfactual possibility and how negation affects this process. For this purpose, we designed a task similar to the one in chapter three. This consisted of 8 stories in which the type of counterexample (alternative vs. disabler) and the concreteness of the negation (concrete vs. abstract) were manipulated. Each of them had three questions: an inference from counterfactuals, another one about the epistemic status and a third one about the underlying cause in the established causal relationship. The results suggest that we tend to construct the counterfactual possibility by retrieving an alternative to the antecedent, rather than by using explicit negation through syntactic elements ("not"). The results also seem to highlight the importance of the developmental nature of the construction of negation in this aspect, with children more easily retrieving concrete alternatives to the negation rather than abstract alternatives. However, no differences are found in adults, probably due to their ability to think with abstract content. Finally, Chapter 5 offers a general discussion of the most relevant results obtained in the different studies. It also discusses some possible practical implications, limitations and future lines of research.