Carey argues that the aspects of categorization that are diagnostic of deep conceptual structure and, by extension, narrow conceptual content, must be distinguished from those aspects that are incidental to categorization tasks. For natural kind concepts, discriminating between these two types of processes is complicated by the role of explanatory stance and the causal history of features in determining category structure.

Cultural variability in self-enhancement is far more pronounced than the authors suggest; the sum of the evidence does not show that East Asians self-enhance in different domains from Westerners. Incorporating this cultural variation suggests a different way of understanding the adaptiveness of self-enhancement: It is adaptive in contexts where positive self-feelings and confidence are valued over relationship harmony, but is maladaptive in contexts where relationship harmony is prioritized.

Bayesian accounts are currently popular in the field of inductive reasoning. This commentary briefly reviews the limitations of one such account, the Rational Model (Anderson 1991b), in explaining how inferences are made about objects whose category membership is uncertain. These shortcomings are symptomatic of what Jones & Love (J&L) refer to as “fundamentalist” Bayesian approaches.

The drug-reinforcement theory explains why humans get engaged in drug taking behavior. This theory posits that drugs of abuse serve as biological rewards by activating the reinforcement system. Although from a psychological and neurobiological perspective this theory is extremely helpful, it does not tell us about the drug-taking motives and motivation of an individual. The definition of drug instrumentalization goals will improve our understanding of individual drug-taking profiles.

Self-deception may be a natural consequence of active goal operation instead of an adaptation for negotiating the social world. We argue that because autonomous goal programs likely drove human judgment and behavior prior to evolution of a central executive or “self,” these goal programs can operate independently to attain their desired end states and thereby produce outcomes that “deceive” the individual.

We are neither as pessimistic nor as optimistic as Elqayam & Evans (E&E). The consequences of normativism have not been uniformly disastrous, even among the examples they consider. However, normativism won't be going away any time soon and in the literature on causal Bayes nets new debates about normativism are emerging. Finally, we suggest that to concentrate on expert reasoners as an antidote to normativism may limit the contribution of research on thinking to basic psychological science.

We dispute Carey's assumption that distinct core cognitive processes employ domain-specific input analyzers to construct proprietary representations. We give reasons to believe that conceptual systems co-opt core components for new domains. Domain boundaries, as well as boundaries between perceptual–motor and conceptual cognitive resources may be useful abstractions, but do not appear to reflect constraints respected by brains and cognitive systems.

This commentary agrees with Mercier and Sperber's (M&S's) thesis on the argumentative function of reasoning but suggests that an account of argument strength is required. A Bayesian account of argument strength (Hahn & Oaksford 2007) shows how the deployment of deductive fallacies, weak inductive arguments, and judgment fallacies such as base-rate neglect, can all be rationally defended in the right argumentative context.

We applaud Müller & Schumann (M&S) for bringing needed attention to the problem of motivation for common non-addictive drug use, as opposed to the usual focus on exotic drugs and addiction. Unfortunately, their target article has many underdeveloped and sometimes contradictory ideas. Here, we will focus on three key issues.

It is timely to assess Bayesian models, but Bayesianism is not a religion. Bayesian modeling is typically used as a tool to explain human data. Bayesian models are sometimes equivalent to other models, but have the advantage of explicitly integrating prior hypotheses with new observations. Any lack of representational or neural assumptions may be an advantage rather than a disadvantage.

We support Enlightenment Bayesianism's commitment to grounding Bayesian analysis in empirical details of psychological and neural mechanisms. Recent philosophical accounts of mechanistic science illuminate some of the challenges this approach faces. In particular, mechanistic decomposition of mechanisms into their component parts and operations gives rise to a notion of levels distinct from and more challenging to accommodate than Marr's.

It is unclear how an argumentative environment would select for better reasoning given three general findings. First, argument rationality typically fails to persuade poor reasoners. Second, reasoned argumentation competes with more persuasive and less rational arguments for limited cognitive resources. Third, those poor at reasoning fail to distinguish between valid and invalid arguments. Reasoning, therefore, is poorly designed for argument.

Elqayam & Evans (E&E) argue that the major objective of research on human thinking should be the development of descriptive theories, and they challenge normativism – “the belief that people ought to conform to a normative standard” (target article, sect. 1, para. 10). I contend that although their argument for the importance of developing descriptive theories is compelling, normative theories are also important, not only for improving thinking but for investigating and understanding it as well.

The adaptive use of drugs, or “drug instrumentalization,” is presented as a reality that the scientific literature has largely ignored. In this commentary, we demonstrate why this concept has limited value from the standpoint of nosology, why it should not be viewed as “adaptive,” and why it has dangerous implications for policy and public health efforts.

Von Hippel & Trivers (VH&T) dismiss in a couple of pages the possible costs of self-deception. But there is a downside to self-deception that they do not consider. This is the loss of psychological insight into deceit by others that blindness to deceit by oneself is likely to entail.

Carey holds that the study of conceptual development bears on the theories of concepts developed by philosophers and psychologists. In this commentary, I scrutinize her claims about the significance of the study of conceptual development.

It's unclear what narrow content is interpersonally shared for concepts that don't originate from core cognition yet are still definitionally and interpretationally primitive. A primary concern is that for these concepts, one cannot draw a principled distinction between inferences that are content determining and those that aren't. The lack of a principled distinction imperils an account of interpersonally shared concepts.

Mere facts about how the world is cannot determine how we ought to think or behave. Elqayam & Evans (E&E) argue that this “is-ought fallacy” undercuts the use of rational analysis in explaining how people reason, by ourselves and with others. But this presumed application of the “is-ought” fallacy is itself fallacious. Rational analysis seeks to explain how people do reason, for example in laboratory experiments, not how they ought to reason. Thus, no ought is derived from an is; and rational analysis is unchallenged by E&E's arguments.

The field of causal learning and reasoning (largely overlooked in the target article) provides an illuminating case study of how the modern Bayesian framework has deepened theoretical understanding, resolved long-standing controversies, and guided development of new and more principled algorithmic models. This progress was guided in large part by the systematic formulation and empirical comparison of multiple alternative Bayesian models.

A consideration of selection pressures on the psychology of argument suggests that fixing the truth value of claims is not the primary criterion for argument generation or evaluation. Instead, argument psychology is designed to change representations in other minds as a way to negotiate conflicts of interest and as a way to signal social coordination.