Tomasello claims that we lack convincing evidence that nonhuman animals manifest a sense of moral obligation (i.e., the concept of fairness) in their group activities. The philosophical analysis of distinctive evidence from ethology, namely group hunting practices among chimpanzees, can help the author appreciate the distinctive character of this behaviour as a display of fairness put into practice.

Yarkoni correctly recognizes that one reason for psychology's generalizability crisis is the failure to account for variance within experiments. We argue that this problem, and the generalizability crisis broadly, is a necessary consequence of the stimulus-response paradigm widely used in psychology research. We point to another methodology, perturbation experiments, as a remedy that is not vulnerable to the same problems.

We argue that Smaldino has not established that group-level traits constitute a unit of selection distinct from selection on individuals, as group-level traits are neither replicators nor interactors. Moreover, we argue that Wimsatt's analysis of emergence and aggregativity supports an understanding of group-level and other emergent traits as explanatorily reducible to the individual level.

The target article proposes an error theory for religious belief. In contrast, moral beliefs are typically not counterintuitive, and some moral cognition and motivation is functional. Error theories for moral belief try to reduce morality to nonmoral psychological capacities because objective moral beliefs seem too fragile in a competitive environment. An error theory for religious belief makes this unnecessary.

This comment expands on Hooks et al.’s criticism of the problematic and overly general uses of “stress” within the microbiota-gut-brain field. The comment concludes that, for the microbiota-gut-brain field (as for other fields drawing on “stress”), much work is yet to be done in terms of how we explore and understand biology vis-à-vis psychology.

The target article advances several original concepts about shamanism, including prospective explanations for how shamanism could express itself in different cultural settings. Although the potential for “innate psychological tendencies” is acknowledged, the target article prematurely dismisses one such hard-wired feature of shamanism: psychosis.

Tomasello et al. provide a new account of cultural uniqueness, one that hinges on a uniquely human motivation to share intentionality with others. We favor an alternative to this motivational account – one that relies on a modular explanation of the primate intention-reading system. We discuss this view in light of recent comparative experiments using competitive intention-reading tasks.

Osiurak and Reynaud highlight the critical role of technical-reasoning skills in the emergence of human cumulative technological culture (CTC), in contrast to previous accounts foregrounding social-reasoning skills as key to CTC. We question their analysis of the available evidence, yet for other reasons applaud the emphasis on causal understanding as central to the adaptive and collaborative dynamics of CTC.

Quilty-Dunn et al. defended the reemergence of language-of-thought hypothesis (LoTH). My commentary builds up implications for the study of the development of our logical capacities. Empirical support for logically augmented LoT systems calls for the investigation of their logical primitives and developmental origin. Furthermore, Quilty-Dunn et al.'s characterization of LoT helps the quest for the foundation of logic by dissociating logical cognition from natural language.

Rips et al. argue that the construction of math schemas roughly similar to the Dedekind/Peano axioms may be necessary for arriving at arithmetical skills. However, they neglect the neo-Fregean alternative axiomatization of arithmetic, based on Hume's principle. Frege arithmetic is arguably a more plausible start for a top-down approach in the psychological study of mathematical cognition than Peano arithmetic.

The metaphor of selfish goals is misguided. Organisms can be considered vessels that further the interests of their genes, but not vessels that further the interests of their goals. Although goals can act at cross-purposes to each other and to longevity, such trade-offs are predicted by evolutionary theory. The metaphor of selfish goals provides no purchase on this problem.