In addition to satisfying a predisposition for exploration, fiction with imaginary worlds may also appeal to morbid curiosity, an adaptive motivation to seek out information about dangerous situations. Most imaginary worlds contain narrative elements of danger, and immersion in such worlds may provide people with information that would be costly to acquire in the real world.

Why has fiction been so successful over time? We make the case that fiction may have properties that enhance both individual and group-level fitness by (a) allowing risk-free simulation of important scenarios, (b) effectively transmitting solutions to common problems, and (c) enhancing group cohesion through shared consumption of fictive worlds.

If recent exploratory traditions tap into evolved psychological dispositions to explore, wouldn't humans be expected to have drawn on such dispositions long before the written word? Trickster oral traditions fill this role in all levels of society, affluence, and on all continents, inverting the boundaries of social worlds and those between humans and animals, fostering cultural innovation.

Aphantasia is a heterogeneous neuropsychological syndrome consisting of the inability to create mental images. We argue that its progressive form may be a harbinger of dementia. Aphantasia may manifest as the inability to create any mental images or to create complex scenes, inability to spontaneously initiate generation of mental images, and/or inability to visualize a sequence of events.

Dubourg and Baumard's paper takes a different, and fruitful, approach to the study of imaginary worlds than what is usually found in Media Studies, but omits certain circumstances and influences that shaped their history; this article argues that psychological or behavioral factors are not enough to explain the growth of imaginary worlds, even as they may be important influences.

Explaining the reasons behind the success of various kinds of fiction is important, but how granular should our explanations be? I suggest that using a less granular, more general hypothesis would allow avoiding some pitfalls, such as using the concept of “imaginary world,” which eludes precise definitions.

We support the idea of applying cultural evolution theory to the study of storytelling, and fiction in particular. However, we suggest that a more plausible link between real and imaginary worlds is the feeling of “presence” we can experience in both of them: we feel present when we are able to correctly and intuitively enact our embodied predictions.

The authors explain our attraction to strange, literary places as resulting from our attraction to strange places in real life. I believe this is correct and important. The aim of the following commentary is to show that their main conclusion is closely related to – even (retrospectively) predictable from – the operation of simulation and the consequences of that operation for storytelling.

While Dubourg and Baumard argue that predisposition toward exploration draws us to fictional environments, they fail to answer their titular question: “Why Imaginary Worlds?” Research in pretend play, psychological distancing, and theatre shows that being “imaginary” (i.e., any type of unreal, rather than only fantastically unreal) makes exploration of any fictional world profoundly different than that of real-life unfamiliar environments.

The UK government implemented national social-distancing measures in response to the global COVID19 pandemic. As a result, many appointments in the National Health Service (NHS) took place virtually, including psychological interventions in out-patient settings. This study explored the experiences of adolescents participating in a dialectical behaviour therapy (DBT-A) programme via teletherapy (i.e. via video or telephone call) in a Children and Adolescent Mental Health Service (CAMHS). Thirteen adolescents with emotion dysregulation and related problems completed an online qualitative survey about their experience and acceptance of DBT-A delivered virtually. Thematic analysis was conducted on the survey data and generated three over-arching themes: (1) sense of loss; (2) feeling uncontained; and (3) benefits of virtual DBT. These over-arching themes were composed of eight subthemes (‘loss of connection with group and therapist’; ‘loss of skills-building opportunities’; ‘limited privacy’; ‘lack of safe therapy space’; ‘difficult endings’; ‘home comforts’; ‘convenience and accessibility’; and ‘easier to participate with others’). This study suggests that adolescents doing virtual DBT-A need approaches that acknowledge and address the additional relational, emotional and practical challenges of online therapy while maintaining fidelity to the evidence-based treatment model. Suggestions for further research and preliminary practice guidelines are discussed.

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.

Awe arises when one experiences something so extraordinary that it defies current understanding, prompting efforts to comprehend the initially incomprehensible. We situate awe within Dubourg and Baumard's framework for the prevalence and psychological underpinnings of imaginary worlds. We argue that imaginary worlds are powerful catalysts of awe, which, in turn, drive important individual and social outcomes.

Dubourg and Baumard posited that preferences for exploration are the key to the popularity in imaginary worlds. This commentary argues that other forms of exploration may also account for the success and appeal of specific types of imaginary worlds, namely self-exploration within interactive imaginary worlds such as videogames.

We assume “Imaginary worlds” to be unreal and unfamiliar: high fantasy. I argue they are real and familiar to authors because they comprise memory elements, which blend experience, knowledge, beliefs and pre-occupations. These “bits and pieces” from memories can generate a world, which readers experience as pure imagination. I illustrate using J.M. Barrie's “Never Land” and J.R.R. Tolkien's “Middle-Earth.”

We received several commentaries both challenging and supporting our hypothesis. We thank the commentators for their thoughtful contributions, bringing together alternative hypotheses, complementary explanations, and appropriate corrections to our model. Here, we explain further our hypothesis, using more explicitly the framework of evolutionary social sciences. We first explain what we believe is the ultimate function of fiction in general (i.e., entertainment) and how this hypothesis differs from other evolutionary hypotheses put forward by several commentators. We then turn to the proximate features that make imaginary worlds entertaining and, therefore, culturally successful. We finally explore how these insights may explain the distribution of imaginary worlds across time, space, age, and social classes.

Human engagement with imaginary worlds pervades history (e.g., Paleolithic cave paintings) and development (e.g., 18-month-olds pretend). In providing a safe environment, separate from the real world, fiction offers the opportunity for simulated exploration regardless of external circumstances. Thus, engagement with imaginary worlds in fiction may afford individuals opportunities to reap benefits and transfer these benefits back to the real world.

The authors argue that children prefer fictions with imaginary worlds. But evidence from the developmental literature challenges this claim. Children's choices of stories and story events show that they often prefer realism. Further, work on the imagination's relation to counterfactual reasoning suggests that an attraction to unrealistic fiction would undermine the imagination's role in helping children understand reality.

Dubourg and Baumard explain why fictional worlds are attractive to consumers. A complete account of fictional worlds, however, should also explain why some people create them. Creation is a costly and time-consuming process that does not resemble exploration but does resemble the culturally universal phenomenon of knowledge specialization.