Uchiyama et al. productively discuss how culture can influence genetic heritability and, by modifying environmental conditions, limit the generalizability of genome-wide association studies (GWASs). Here, we supplement their account by highlighting how recent changes in culture and institutions in industrialized, westernized societies – such as increased female workforce participation – may have increased assortative mating. This alters the distribution of genotypes themselves, increasing heritability and phenotypic variance, and may be detectable using the latest methods.

The 29 commentaries amplified our key arguments; offered extensions, implications, and applications of the framework; and pushed back and clarified. To help forge the path forward for cultural evolutionary behavioral genetics, we (1) focus on conceptual disagreements and misconceptions about the concepts of heritability and culture; (2) further discuss points raised about the intertwined relationship between culture and genes; and (3) address extensions to the proposed framework, particularly as it relates to cultural clusters, development, and power. These commentaries, and the deep engagement they represent, reinforce the importance of integrating cultural evolution and behavioral genetics.

The free energy principle, an influential framework in computational neuroscience and theoretical neurobiology, starts from the assumption that living systems ensure adaptive exchanges with their environment by minimizing the objective function of variational free energy. Following this premise, it claims to deliver a promising integration of the life sciences. In recent work, Markov blankets, one of the central constructs of the free energy principle, have been applied to resolve debates central to philosophy (such as demarcating the boundaries of the mind). The aim of this paper is twofold. First, we trace the development of Markov blankets starting from their standard application in Bayesian networks, via variational inference, to their use in the literature on active inference. We then identify a persistent confusion in the literature between the formal use of Markov blankets as an epistemic tool for Bayesian inference, and their novel metaphysical use in the free energy framework to demarcate the physical boundary between an agent and its environment. Consequently, we propose to distinguish between “Pearl blankets” to refer to the original epistemic use of Markov blankets and “Friston blankets” to refer to the new metaphysical construct. Second, we use this distinction to critically assess claims resting on the application of Markov blankets to philosophical problems. We suggest that this literature would do well in differentiating between two different research programmes: “inference with a model” and “inference within a model.” Only the latter is capable of doing metaphysical work with Markov blankets, but requires additional philosophical premises and cannot be justified by an appeal to the success of the mathematical framework alone.

Markov blankets – statistical independences between system and environment – have become popular to describe the boundaries of living systems under Bayesian views of cognition. The intuition behind Markov blankets originates from considering acyclic, atemporal networks. In contrast, living systems display recurrent, nonequilibrium interactions that generate pervasive couplings between system and environment, making Markov blankets highly unusual and restricted to particular cases.

Bruineberg and colleagues report a striking confusion, in which the formal Bayesian notion of a “Markov blanket” has been frequently misunderstood and misapplied to phenomena of mind and life. I argue that misappropriation of formal concepts is pervasive in the “predictive processing” literature, and echo Richard Feynman in suggesting how we might resist the allure of cargo cult computationalism.

The principal target of this article is the reification Bruineberg et al. perceive of formalism within the literature on the variational free energy minimization (VFEM) framework. The authors do not provide a definition of reification, as none yet exists. Here I offer one. On this definition, the objects of the authors' critiques fall short of full-blown reification – as do the authors themselves.

Bruineberg et al. argue that one ought not confuse the map (model) for the territory (reality) and delineate a distinction between innocuous Pearl blankets and metaphysically laden Friston blankets. I argue that all we have are models, all knowledge is conditional, and that if there is a Pearl/Friston distinction, it is a matter of the domain of application: latents or observations. This suggests that, if anything, Friston blankets may inherit philosophical significance previously assigned to observations.

Over-flexibility in the definition of Friston blankets obscures a key distinction between observational and interventional inference. The latter requires cognizers form not just a causal representation of the world but also of their own boundary and relationship with it, in order to diagnose the consequences of their actions. We suggest this locates the blanket in the eye of the beholder.

Assigning to Pearl blankets an instrumental, a “pure” formal role, tacitly delegates the thorny question of mapping the “murky” territory to empirical sciences. But this move side-lines the problem, and does not offer a solution to the question: How do we relate the formal properties of an agent's model of the world to the real properties of the world itself?

Bruineberg and colleagues highlight work using Markov blankets to demarcate the bounds of the mind. This echoes earlier attempts to demarcate the bounds of the mind from a dynamical systems perspective. Advocates of mechanistic explanation have challenged the dynamical approach to independently motivate the application of the formalism, a challenge that Markov blanket theorists must also meet.

Bruineberg and collaborators distinguish three philosophical positions about the status of Markov blankets in the context of active inference modelling, namely: literalism, realism, and instrumentalism. They criticize the first two positions and suggest that instrumentalism is “less problematic but also less interesting” (sect. 6.1.2, para. 5) Here, I sketch how literalists and realists might reply to Bruineberg et al.'s criticisms, and I explain why instrumentalism is more interesting and contentious than what Bruineberg and collaborators suggest.

Bruineberg and colleagues argue that a realist interpretation of Markov blankets inadvertently relies upon unfounded assumptions. However, insofar as their diagnosis is accurate, their prescribed instrumentalism may ultimately prove insufficient as a complete remedy. Drawing upon a process-based perspective on living systems, we suggest a potential way to avoid some of the assumptions behind problems described by Bruineberg and colleagues.

I argue that there is no viable development of the instrumentalist inference within a model research program. I further argue that both Friston and Pearl blankets are not the right sort of tool to settle debates on philosophical internalism and externalism. For these reasons, the inference within a model program is far less promising than the target article suggests.

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.

It is a pleasure to comment on Bruineberg et al. – who raise some interesting questions of a philosophical and technical nature. I will try to answer three questions posed by the authors. Are Pearl and Friston blankets different things? Are Markov blankets used in an ontological sense? Is there a privileged Markov blanket?

Neuroscience needs theory. Ideas without data are blind, and yet mechanisms without concepts are empty. Friston's free energy principle paradigmatically illustrates the power and pitfalls of current theoretical biology. Mighty metaphors, turned into mathematical models, can become mindless metaphysics. Then, seeking to understand everything in principle, we may explain nothing in practice. Life can't live in a map.

In this commentary, I first acknowledge points of common ground with the target article by Bruineberg and colleagues. Then, I consider how certain ambiguities could be resolved by considering spatiotemporal constraints on causality. In particular I show how blanket closure emerges from localized interactions between temporally separable subsystems, and how this points to valuable directions of future research. Finally, I close with a process note discussing the allegorical implications of the authors' creative title.

We target the ontological and epistemological ramifications of the proposed distinction between Friston and Pearl blankets. We emphasize the need for empirical testing next to computational modeling. A peculiar aspect of the free energy principle (FEP) is its purported support of radically opposed ontologies of the mind. In our view, the objective ontological aspiration itself should be rejected for a pragmatic instrumentalist view.

We challenge the authors' view that Markov blankets are illicitly reified when used to describe organismic boundaries. We do this both on general methodological grounds, where we appeal to a form of structural realism derived from Bayesian cognitive science to dissolve the problem, and by rebutting specific arguments in the target article.

Bruineberg and colleagues' critique of Friston blankets relies on what we call the “literalist fallacy”: the assumption that in order for Friston blankets to represent real boundaries, biological systems must literally possess or instantiate Markov blankets. We argue that it is important to distinguish a realist view of Friston blankets from the literalist view of Bruineberg and colleagues’ critique.