What inductive biases must be incorporated into multi-agent artificial intelligence models to get them to capture high-fidelity imitation? We think very little is needed. In the right environments, both instrumental- and ritual-stance imitation can emerge from generic learning mechanisms operating on non-deliberative decision architectures. In this view, imitation emerges from trial-and-error learning and does not require explicit deliberation.

We argue that music can serve as a time-sensitive lens into the interplay between instrumental and ritual stances in cultural evolution. Over various timescales, music can switch between pursuing an end goal or not, and between presenting a causal opacity that is resolvable, or not. With these fluctuations come changes in the motivational structures that drive innovation versus copying.

While I agree with the distinction between expedient and proper ways of action, I find Jagiello et al.'s account of “stance switching” debatable. Fundamental to theories of cultural evolution is the fact that the shared environment is indefinitely rich, in which individuals are provided with opportunities for learning to tune themselves to specific affordances that are relevant to emerging situations.

Biologists have replaced the metaphor of “genetic transmission” with a detailed account of the molecular mechanisms underlying the phenomenon which Darwin referred to as “like produces like.” Cultural evolution theorists, in contrast, continue to appeal to “imitation” or “copying.” The notion of ritual and instrumental stances does not resolve this issue, and ignores the institutions in which people live.

Understanding how culture evolves in society is an extremely difficult task. The bifocal stance theory (BST) deploys two copying strategies which can be linked to dual-system theories of behavior. BST would benefit from incorporating results from these theories, such as the evolution of attention to goals or steps of a behavioral sequence, and the role of the environment in prompting different copying strategies.

Jagiello and colleagues offer a bifocal stance theory of cultural evolution for understanding how individuals flexibly choose between instrumental and ritual stances in social learning. We argue that the role of culture, developmental age-related differences, and the intersectionality of these and other individual's identities need to be more fully considered in this theoretical framework.

Jagiello et al.'s bifocal stance theory provides a useful theoretical framework for attempting to understand the connection between greater adherence to traditional norms and greater sensitivity to threats in the world. Here, we examine the implications of the instrumental and ritual stances with regard to various evolutionary explanations for traditionalism–threat sensitivity linkages.

The bifocal stance theory (BST) focuses on cultural evolution without alluding to associated processes in linguistic evolution and language use. The authors briefly comment on language acquisition but leave underexplored the applicability of BST to linguistic evolution, to changes of language representations, and to possible consequences for constructing social identity, based on, for example, collective resilience processes within language communities.

Actions that do not have instrumental goals can communicate social goals that are not rituals. Many non-instrumental actions such as bowing or kissing communicate a commitment to or roles in dyadic relationships. What is unclear is when people understand such actions in terms of ritual and when they understand them in terms of relationships.

In this commentary we advance Jagiello et al.'s proposal by zooming in on the possible evolutionary origins of the “bifocal stance” that may have enabled a major transition in human cultural evolution, arguing that the evolution of the bifocal stance was driven by an explosion in cultural complexity arising from cooperative foraging, which led to a feedback loop between the ritual and instrumental stances.

We propose that human social learning is subject to a trade-off between the cost of performing a computation and the flexibility of its outputs. Viewing social learning through this lens sheds light on cases that seem to violate bifocal stance theory (BST) – such as high-fidelity imitation in instrumental action – and provides a mechanism by which causal insight can be bootstrapped from imitation of cultural practices.

The central idea of the bifocal stance theory (BST) by Jagiello et al. has substantial relevance to scientific research. Both tradition-following and exploration-innovation are important in science and researchers subconsciously try to optimize their strategies. We outline three important dimensions of this optimization and argue that attempts to understand this complex process can help us design better science education, research training, investigation, and science publication.

The principal contrasts that Jagiello et al. highlight are among many cultural transmission biases we now know of. I suggest they are also reflected more widely in social learning decisions among nonhuman animal cultures governing whether cultural innovations spread, or are instead over-ridden by immigrants' conformity in their new group. Such conformity may serve either informational or social-integrative functions.

The authors make a distinction between instrumental copying behavior in which there is a clear reward for the copying behavior and social copying (traditions) in which the rewards for copying are less clear. However, I see no reason to distinguish between the two. We are social animals, for whom copying traditions have important rewards, those of affiliation.

The bifocal stance theory (BST) of cultural evolution has prompted a wide-ranging discussion with broadly three aims: to apply the theory to novel contexts; to extend the conceptual framework; to offer critical feedback on various aspects of the theory. We first discuss BST's relevance to the diverse range of topics which emerged from the commentaries, followed by a consideration of how our framework can be supplemented by and compared to other theories. Lastly, the criticisms that were raised by a subset of commentaries allow us to clarify parts of our theory.

Imaginary worlds are extremely successful. The most popular fictions produced in the last few decades contain such a fictional world. They can be found in all fictional media, from novels (e.g., Lord of The Rings and Harry Potter) to films (e.g., Star Wars and Avatar), video games (e.g., The Legend of Zelda and Final Fantasy), graphic novels (e.g., One Piece and Naruto), and TV series (e.g., Star Trek and Game of Thrones), and they date as far back as ancient literature (e.g., the Cyclops Islands in The Odyssey, 850 BCE). Why such a success? Why so much attention devoted to non-existent worlds? In this paper, we propose that imaginary worlds co-opt our preferences for exploration, which have evolved in humans and nonhuman animals alike, to propel individuals toward new environments and new sources of reward. Humans would find imaginary worlds very attractive for the very same reasons, and under the same circumstances, as they are lured by unfamiliar environments in real life. After reviewing research on exploratory preferences in behavioral ecology, environmental esthetics, neuroscience, and evolutionary and developmental psychology, we focus on the sources of their variability across time and space, which we argue can account for the variability of the cultural preference for imaginary worlds. This hypothesis can, therefore, explain the way imaginary worlds evolved culturally, their shape and content, their recent striking success, and their distribution across time and populations.

Imaginary worlds are not a consequence of humans' exploratory tendencies as argued in the target article but a recent spinoff of a strong human tendency to create imaginary realities, that is, versions of how the world works that are fabricated (although we believe they are real) in order to allow us to believe we understand it and can control it.

Evidence from developmental psychology on children's imagination is currently too limited to support Dubourg and Baumard's proposal and, in several respects, it is inconsistent with their proposal. Although children have impressive imaginative powers, we highlight the complexity of the developmental trajectory as well as the close connections between children's imagination and reality.

Dubourg and Baumard mention a potential role for the human drive to systemise as a factor motivating interest in imaginary worlds. Given that hyperexpression of this trait has been linked with autism (Baron-Cohen, 2002, 2006), we think this raises interesting implications for how those on the autism spectrum may differ from the neurotypical population in their engagement with imaginary worlds.

We argue that the generation and enjoyment of imaginary worlds do not necessarily rely on an evolved preference for exploration. Rather, we suggest that culture is shaped by socioecological facts on the ground, and we hypothesize about the role of residential mobility, specifically, as an important factor in the popularity of imagined spaces.