According to the default interventionist dualprocess account of reasoning, belief-based responses to reasoning tasks are based on Type 1 processes generated by default, which must be inhibited in order to produce an effortful, Type 2 output based on the validity of an argument. However, recent research has indicated that reasoning on the basis of beliefs may not be as fast and automatic as this account claims.In three experiments, we presented participants with a reasoning task that was to be completed while they were generating random numbers (RNG). We used the novel methodology introduced by Handley, Newstead & Trippas (Journal of Experimental Psychology: Learning, Memory, and Cognition, 37, 28-43, 2011), which required participants to make judgments based upon either the validity of a conditional argument or the believability of its conclusion. The results showed that belief-based judgments produced lower rates of accuracy overall and were influenced to a greater extent than validity judgments by the presence of a conflict between belief and logic for both simple and complex arguments. These findings were replicated in Experiment3, in which we controlled for switching demands in a blocked design. Across all three experiments, we found a main effect of RNG, implying that both instructional sets require some effortful processing. However, in the blocked design RNG had its greatest impact on logic judgments, suggesting that distinct executive resources may be required for each type of judgment. We discuss the implications of our findings for the default interventionist account and offer a parallel competitive model as an alternative interpretation for our findings.

Classic dual process theories of human reasoning attribute explicit reasoning to effortful, deliberative thinking. According to these models, intuitive processes lack any access to the formal rules of logic and probability and hence rely exclusively on superficial problem features to determine a response. However, in recent years, researchers have demonstrated that reasoners are able to solve simple logical or probabilistic problems relatively automatically, a capability which has been called ‘logical intuition’. In four experiments, we instructed participants to judge the validity (Experiments 1 and 4), likeability (Experiments 1, 2, and 3) and physical brightness (Experiments 2, 3, and 4) of the conclusion to several reasoning problems. Brightness judgments were made by evaluating the font shade brightness of the argument’s conclusion. Participants were also asked to complete a range of individual differences measures, drawing on cognitive ability and cognitive style, in order to evaluate the extent to which ‘logical intuitions’ were linked to measures of deliberative reasoning. The results showed that participants judged the conclusion of logically valid statements to be more valid, more likable and more physically bright. Participants with higher cognitive ability and unlimited processing time showed greater effects of logical validity in their liking judgments (varied across experiments). However, these effects were absent in the brightness tasks, suggesting that logic effects observed under instructions to judge conclusion brightness are a purer measure of ‘logical intuition’. We discuss the implications of our findings for recent dual process theories of human reasoning.

In stage 1 classroom conversations between sixteen teachers and their pre-lingually deaf children were videotaped and analysed to examine both the styles used by teachers in controlling conversation and the functions pursued in dialogue. In stage 2 a sub-sample of four teachers with twenty children of known hearing losses and non-verbal intelligence was analysed in greater detail to examine relationships between these factors, teaching styles and the child's performance in dialogue. The analyses show that deaf children respond in a similar fashion to young hearing children in the way they react to different styles of teacher talk; that teachers differ in the functions they pursue in conversation; and that functions change as a consequence of the child's hearing loss but not mental age. The implications of the findings for linguistic development in pre-lingually deaf children are explored.

Recent research suggests that reasoners are able to draw simple logical or probabilistic inferences relatively intuitively and automatically, a capacity which has been termed "logical intuition" (see, for example, De Neys & Pennycook, 2019). A key finding in support of this interpretation is that conclusion validity consistently interferes with judgments of conclusion believability, suggesting that information about logical validity is available quickly enough to interfere with belief judgments. In this paper we examined whether logical intuitions arise because reasoners are sensitive to the logical features of problem or another structural feature that just happens to aligns with logical validity. In three experiments (N = 113, 137, and 254), we presented participants with logical (determinate) and pseudological (indeterminate) arguments and asked them to judge the validity or believability of the conclusion. Logical arguments had determinately valid or invalid conclusions, whereas pseudo-logical arguments were all logically indeterminate, but some were pseudo-valid (possible 'strong' arguments) and others pseudo-invalid (possible 'weak' arguments). Experiments 1 and 2 used simple Modus Ponens and Affirming the Consequent structures; Experiment 3 used more complex Denying the Antecedent and Modus Tollens structures. In all three experiments, we found that pseudo-validity interfered with belief judgments to the same extent as real validity. Altogether, these findings suggest that whilst people are able to draw inferences intuitively, and these inferences impact on belief judgments, they are not 'logical intuitions.' Rather, the intuitive inferences are driven by the processing of more superficial structural features that happen to align with logical validity.

The Default Interventionist account suggests that by default, we often generate belief-based responses when reasoning and find it difficult to draw the logical inference. Recent research, however, shows that in some instances belief judgments take longer, are more prone to error and are more affected by cognitive load. One interpretation is that some logical inferences are available automatically and require intervention in order to respond according to beliefs. In two experiments, we investigate the effortful nature of belief judgments and the automaticity of logical inferences by increasing the inhibitory demands of the task. Participants were instructed to judge conclusion validity, believability and either font colour or font style, to increase the number of competing responses. Results showed that conflict more strongly affects judgments of believability than validity and when inhibitory demands are increased, the validity of an argument impacts more on belief judgments. These findings align with the new Parallel Processing model of belief bias.