Action comprehension in non-human primates: motor simulation or inferential reasoning?

Some argue that action comprehension is intimately connected with the observer's own motor capacities, whereas others argue that action comprehension depends on non-motor inferential mechanisms. We address this debate by reviewing comparative studies that license four conclusions: monkeys and apes extract the meaning of an action (i) by going beyond the surface properties of actions, attributing goals and intentions to the agent; (ii) by using environmental information to infer when actions are rational; (iii) by making predictions about an agent's goal, and the most probable action to obtain the goal given environmental constraints; (iv) in situations in which they are physiologically incapable of producing the actions. Motor theories are, thus, insufficient to account for primate action comprehension in the absence of inferential mechanisms.     

Is belief reasoning automatic?

Understanding the operating characteristics of theory of mind is essential for understanding how beliefs, desires, and other mental states are inferred, and for understanding the role such inferences could play in other cognitive processes. We present the first investigation of the automaticity of belief reasoning. In an incidental false-belief task, adult subjects responded more slowly to unexpected questions concerning another person's belief about an object's location than to questions concerning the object's real location. Results in other conditions showed that responses to belief questions were not necessarily slower than responses to reality questions, as subjects showed no difference in response times to belief and reality questions when they were instructed to track the person's beliefs about the object's location. The results suggest that adults do not ascribe beliefs to agents automatically.     

Is reasoning from counterfactual antecedents evidence for counterfactual reasoning?

In most developmental studies the only error children could make on counterfactual tasks was to answer with the current state of affairs. It was concluded that children who did not show this error are able to reason counterfactually. However, children might have avoided this error by using basic conditional reasoning (Rafetseder, Cristi-Vargas, & Perner, 2010). Basic conditional reasoning takes an antecedent, which like in counterfactual reasoning can be counter to fact, and combines it with a conditional (or set of conditionals reflecting knowledge of how the world works) to draw a likely conclusion. A critical feature of counterfactual reasoning then is that these additional assumptions be modelled after the actual events to which the counterfactual is taken to be counterfactual. In contrast in basic conditional reasoning one enriches the given antecedent with any plausible assumptions. In our tasks basic conditional reasoning leads to different answers than counterfactual reasoning. For instance, a doctor, sitting in the park with the intention to read a paper, is called to an emergency at the swimming pool. The question, "if there had been no emergency, where would the doctor be?" should counterfactually be answered "in the park". But ignoring the doctor's intentions and just reasoning on plausible grounds one might answer: "in the hospital". Only by 6 years, did children give mostly correct answers.     

Is reasoning from counterfactual antecedents evidence for counterfactual reasoning?

In most developmental studies the only error children could make on counterfactual tasks was to answer with the current state of affairs. It was concluded that children who did not show this error are able to reason counterfactually. However, children might have avoided this error by using basic conditional reasoning (Rafetseder, Cristi-Vargas, & Perner, 2010 Perner, J. and Rafetseder, E. 2010. “Counterfactual and other forms of conditional reasoning: Children lost in the nearest possible world”. In Understanding counterfactuals/Understanding causation, Edited by: Hoerl, C., McCormack, T. and Beck, S. R. New York: Oxford University Press.  [Google Scholar]). Basic conditional reasoning takes background assumptions represented as conditionals about how the world works. If an antecedent of one of these conditionals is provided by the task, then a likely conclusion can be inferred based only on background assumptions. A critical feature of counterfactual reasoning is that the selection of these additional assumptions is constrained by actual events to which the counterfactual is taken to be counterfactual. In contrast, in basic conditional reasoning one enriches the given antecedent with any plausible assumptions, unconstrained by actual events. In our tasks basic conditional reasoning leads to different answers from counterfactual reasoning. For instance, a doctor, sitting in the park with the intention of reading a paper, is called to an emergency at the swimming pool. The question, “If there had been no emergency, where would the doctor be?” should counterfactually be answered “in the park”. But by ignoring the doctor's intentions, and just reasoning from premises about the default location of a hospital doctor who has not been called out to an emergency, one might answer: “in the hospital”. Only by 6 years of age did children mostly give correct answers.     

Is everyday causation deterministic or probabilistic?

One view of causation is deterministic: A causes B means that whenever A occurs, B occurs. An alternative view is that causation is probabilistic: the assertion means that given A, the probability of B is greater than some criterion, such as the probability of B given not-A. Evidence about the induction of causal relations cannot readily decide between these alternative accounts, and so we examined how people refute causal assertions. In four experiments most participants judged that a single counterexample of A and not-B refuted assertions of the form, A causes B. And, as a deterministic theory based on mental models predicted, participants were more likely to request multiple refutations for assertions of the form, A enables B. Similarly, refutations of the form not-A and B were more frequent for enabling than causal assertions. Causation in daily life seems to be a deterministic concept.     

Dual processes in reasoning?

Previous results have shown that the introduction of negatives into the sentences used in a deductive problem affected behavior in a systematic way which was independent of the logical structure of the problem. In the present investigation, the subjects were asked to justify their responses when reasoning about such sentences. In accordance with previous results, the responses were dominated by the terms in the sentences regardless of whether they were negated. However, the justifications did vary when negatives were introduced in accordance with the logical consequences of the responses. The interpretation of these justifications as causes of behavior seemed implausible. It was suggested that they were rationalizations, or that there was at least some form of dual processing between behavior and conscious thought.     

Is handedness just response bias?

Although most people prefer to use the right hand for unimanual tasks, it is unknown whether handedness arises from response bias. Whether it does is a question inspired by signal detection theory. We drew on the framework of signal detection theory to assess bias and sensitivity in hand choice by asking right-handers to choose between two tasks—one performed with the left hand, and one performed with the right. For some participants, the left-hand task stayed constant while the right-hand task was varied. For other participants, the right-hand stayed constant while the left-hand task was varied. We reasoned that if hand preference only reflected bias, participants would choose the generally preferred hand to the same degree, regardless of whether its task was constant or varied. Our participants followed this strategy only to some extent, suggesting that bias and sensitivity both contribute to hand preference.     

Is evil just very wrong?

Is evil a distinct moral concept? Or are evil actions just very wrong actions? Some philosophers have argued that evil is a distinct moral concept. These philosophers argue that evil is qualitatively distinct from ordinary wrongdoing. Other philosophers have suggested that evil is only quantitatively distinct from ordinary wrongdoing. On this view, evil is just very wrong. In this paper I argue that evil is qualitatively distinct from ordinary wrongdoing. The first part of the paper is critical. I argue that Luke Russell’s attempt to show that evil is only quantitatively distinct from ordinary wrongdoing fails. Russell’s argument fails because it is based on an implausible criterion for determining whether two concepts are qualitatively distinct. I offer a more plausible criterion and argue that based on this criterion evil and wrongdoing are qualitatively distinct. To help make my case, I sketch a theory of evil which makes a genuinely qualitative distinction between evil and wrongdoing. I argue that we cannot characterize evil as just very wrong on plausible conceptions of evil and wrongdoing. I focus on act-consequentialist, Kantian, and contractarian conceptions of wrongdoing.     

Tests of inferential reasoning by exclusion in Clark’s nutcrackers (Nucifraga columbiana)

We examined inferential reasoning by exclusion in the Clark’s nutcracker (Nucifraga columbiana) using two-way object-choice procedures. While other social scatter-hoarding corvids appear capable of engaging in inferential reasoning, it remains unclear if the relatively less social nutcracker is able to do so. In an initial experiment, food was hidden in one of two opaque containers. All of the birds immediately selected the baited container when shown only the empty container during testing. We subsequently examined the nutcrackers in two follow-up experiments using a task that may have been less likely to be solved by associative processes. The birds were trained that two distinctive objects were always found hidden in opaque containers that were always positioned at the same two locations. During testing, one of the two objects was found in a transparent “trash bin” and was unavailable. The birds were required to infer that if one of the objects was in the “trash,” then the other object should still be available in its hidden location. Five out of six birds were unable to make this inference, suggesting that associative mechanisms likely accounted for our earlier results. However, one bird consistently chose the object that was not seen in the “trash,” demonstrating that nutcrackers may have the ability to use inferential reasoning by exclusion to solve inference tasks. The role of scatter hoarding and social organization is discussed as factors in the ability of corvid birds to reason.     

Is the conjunction fallacy tied to probabilistic confirmation?

Crupi et al. (2008) offer a confirmation-theoretic, Bayesian account of the conjunction fallacy—an error in reasoning that occurs when subjects judge that Pr(h ₁ & h ₂|e) > Pr(h ₁|e). They introduce three formal conditions that are satisfied by classical conjunction fallacy cases, and they show that these same conditions imply that h ₁ & h ₂ is confirmed by e to a greater extent than is h ₁ alone. Consequently, they suggest that people are tracking this confirmation relation when they commit conjunction fallacies. I offer three experiments testing the merits of Crupi et al.’s account specifically and confirmation-theoretic accounts of the conjunction fallacy more generally. The results of Experiment 1 show that, although Crupi et al.’s conditions do seem to be causally linked to the conjunction fallacy, they are not necessary for it; there exist cases that do not meet their three conditions in which subjects still tend to commit the fallacy. The results of Experiments 2 and 3 show that Crupi et al.’s conditions, and those offered by other confirmation-theoretic accounts of the fallacy, are not sufficient for the fallacy either; there exist cases that meet all three of CFT’s conditions in which subjects do not tend to commit the fallacy. Additionally, these latter experiments show that such confirmation-theoretic conditions are at best only weakly causally relevant to the presence of the conjunction fallacy. Given these findings, CFT’s account specifically, and any general confirmation-theoretic account more broadly, falls short of offering a satisfying explanation of the presence of the conjunction fallacy.     

Is case-based reasoning a source of knowledge generalisation?

This study examines the link between case-based reasoning and knowledge generalisation. Experiment 1 showed that case-based reasoning is not in itself a source of generalisation. In this experiment, subjects were able to adapt knowledge acquired during analysis of an example in order to successfully solve a very similar problem. But immediately afterwards, they failed on a problem symmetrical to the one they had just solved. Experiments 2A and 2B showed, in this same situation, that it is possible to lead subjects to generalise simply by stating that the practice problems were similar to the examples. These findings suggest that knowledge generalisation accompanying case-based reasoning is the result of a process that must be actively implemented by the subject, and not an automatic outcome of the source-to-target transfer.     

Is conditional reasoning related to mathematical problem solving?

The current study aimed to investigate the relation between conditional reasoning, which is a common type of logical reasoning, and children's mathematical problem solving. A sample of 124 fourth graders was tested for their conditional reasoning skills and their mathematical problem solving skills, as well as a list of control variables (e.g., IQ, working memory, reading) and potential mediators (number sentence construction and computation). The children's ability to make modus ponens (MP) inferences significantly predicted their mathematical problem solving skills, even after controlling for the potential confounding variables. The relation was mediated by the number sentence construction skills. The findings, in addition to supporting the link between conditional reasoning and mathematics, further indicate that the ability to process relations may be the mechanism underlying the relation. Theoretical and practical implications are discussed.     

Is all therapy just a placebo effect?

The epistemological soundness of controlled clinical trials is questioned. It is argued that the real effect of therapies cannot be determined by such experiments because there is a significant interaction between the placebo effect and real effect created by the individual therapist and treatment situation which, however, is neglected in controlled clinical trials. This critical standpoint is supported by several pharmacological examples.     

Is there more in a happy face than just a big smile?

Happy faces involve appearance changes in the mouth (the smile) and eye region (e.g., narrowing of the eye opening). The present experiments investigated whether the recognition of happy faces is achieved on the basis of the smile alone or whether information in the eye region is also used. A go/no-go task was used in which participants responded to happy faces and withhold a response to nonhappy distractors. The presence/absence of the expressive cues in the eyes did not affect recognition accuracy but reaction times were slightly longer for smiles without expressive cues in the eyes. This delay was not obtained when the top and the bottom halves of the faces were misaligned, or when the distractor was changed from a top-dominant to a bottom-dominant facial expression (i.e., from anger to disgust). Together, these results suggest that the eyes may have a modest effect on speeded recognition of happy faces although the presence of this effect may depend on task context.