The reflectance types that Byrne & Hilbert identify with colors count as types only in a way that is more dependent on, and more relative to color perceivers, than their account suggests. Their account of perceptual content may be overly focused on input conditions and distal causes.

Boyer & Petersen (B&P) lay out an evolutionarily grounded framework to produce concrete, testable predictions about economic phenomena. We commend this step forward, but suggest the framework requires more consideration of cultural contexts that provide necessary input for cognitive systems to operate on. We discuss the role of culture when examining both evolved cognitive systems and social exchange contexts.

Hurford argues that propositions of the form PREDICATE(x) represent conceptual structures that predate language and that can be explicated in terms of neural structure. I disagree, arguing that such predicates are descriptions of limited aspects of brain function, not available as representations in the brain to be exploited in the frog or monkey brain and turned into language in the human.

Heritability is not a measure of the relative contribution of nature vis-à-vis nurture, nor is it the phenotypic variance explained by or because of genetic variance. Heritability is a correlative value. The evolutionary and developmental processes associated with human culture challenge the use of “heritability” for understanding human behavior.

Autism spectrum disorder (ASD) subjects can present temporary behaviors of acute agitation and aggressiveness, named problem behaviors. They have been shown to be consistent with the self-organized criticality (SOC), a model wherein occasionally occurring “catastrophic events” are necessary in order to maintain a self-organized “critical equilibrium.” The SOC can represent the psychopathology network structures and additionally suggests that they can be considered as self-organized systems.

We argue that Whitehouse's group-based model neglects two key contextual variables: environmental threats and ideology. Environmental threats lead to extremism outside of group settings and predispose individuals toward joining ideologically zealous groups. Ideologies and environmental threats can also explain why certain groups adopt norms that encourage violent self-sacrifice.

Classification schemes are useful when they elucidate common underlying mechanisms, bring together diverse examples, or illustrate gaps in knowledge for empirical investigation. Kline's scheme merges different approaches, but is orthogonal to existing schemes and overemphasizes evolved specializations, potentially at the detriment of clarifying teaching processes. Focus on underlying mechanisms, what is learned, and consequences for information transfer may provide additional utility.

Uchiyama et al. present a dual inheritance framework for conceptualizing how behavioural genetics and cultural evolution interact and affect heritability. We posit that to achieve a holistic and nuanced representation of the cultural environment and evolution against which genetic effects should be evaluated, it is imperative to consider the multiple geographic cultural layers impacting individuals and genetic heritability.

We feel exhausted after working mentally hard even while just sitting on a chair, suggesting the concept of cognitive vigor. Do movement vigor and cognitive vigor share control mechanisms? Functions of the basal ganglia-cortical circuits, which are regulated by the midbrain dopaminergic system, appear to underlie both movement vigor and cognitive vigor.

The claims that learning systems must build causal models and provide explanations of their inferences are not new, and advocate a cognitive functionalism for artificial intelligence. This view conflates the relationships between implicit and explicit knowledge representation. We present recent evidence that neural networks do engage in model building, which is implicit, and cannot be dissociated from the learning process.

Cushman argues that the function of rationalization is to attribute mental representations to ourselves, thereby making these representations available for future planning. I argue that such attribution is often not necessary and sometimes maladaptive. I suggest a different explanation of rationalization: making representations available to other agents, to facilitate cooperation, transmission, and the ratchet effect that underlies cumulative cultural evolution.

With respect to De Dreu and Gross's article, we comment on the psychological functions for attack and defense, focusing on associations between individual differences in psychopathic personality traits and the behavioral patterns observed in attack-defense conflicts. We highlight the dimensional nature of psychopathy and formulate hypothetical associations between distinct traits, their different behavioral outcomes, and associated brain mechanisms.

Although compelling and insightful, the proposal by Uchiyama et al. largely neglects within-person change over time, arguably the central topic of interest within their framework. Longitudinal behavioural genetics modelling suggests that the heritability of trajectories is low, in contrast to high and increasing cross-sectional heritability across development. Better understanding of the mechanisms of trajectories remains a crucial outstanding challenge.

We suggest that the accounts offered by the target articles could be strengthened by acknowledging the role of group selection and cultural niche construction in shaping the evolutionary trajectory of human music. We argue that group level traits and highly variable cultural niches can explain the diversity of human song, but the target articles' accounts are insufficient to explain such diversity.

Norenzayan et al. suggest that Big Gods can be replaced by Big Governments. We examine forms of social and self-monitoring and ritual practice that emerged in Classical China, heterarchical societies like those that emerged in pre-Columbian Mesoamerica, and the contemporary Zapatista movement of Chiapas, and we recommend widening the hypothesis space to include these alternative forms of social organization.

Analysis provided in The Emperor's New Markov Blankets reveals that there is limited potential for practical application of Pearl and Friston blankets. However, Bruineberg and colleagues' analysis includes a simple diagram that has potential to better enable shared understanding of interactions between free energy principle constructs during the design and implementation of biosocial–technical systems.

Singh's analysis of shamanism is regarded as a contribution to the evolutionary study of healing encounters and evolutionary medicine. Shamans must create convincing healing spectacles, while sick individuals must convincingly express symptoms and suffering to motivate community care. Both have a shared interest in convincing onlookers. This is not restricted to shamanic treatment, but is still true in modern medical care.

Zwaan et al. and others discuss the importance of the inevitable differences between a replication experiment and the corresponding original experiment. But these discussions are not informed by a principled, quantitative framework for taking differences into account. Bayesian confirmation theory provides such a framework. It will not entirely solve the problem, but it will lead to new insights.

Traditional statistical model evaluation typically relies on goodness-of-fit testing and quantifying model complexity by counting parameters. Both of these practices may result in overfitting and have thereby contributed to the generalizability crisis. The information-theoretic principle of minimum description length addresses both of these concerns by filtering noise from the observed data and consequently increasing generalizability to unseen data.