The central concept in Lee and Schwarz's (L&S's) model is grounded procedures of separation. These are argued to link sensorimotor processes to cognitive processes, specifically physical cleansing to mental dissociation. The concept has to do some heavy lifting to piece together various phenomena: It is more or less explicitly argued to be culturally universal. It is thought to be activated by the emotion of disgust, by engaging in actual cleansing without prior disgust, and even by only remotely associated behavior such as enclosing a note in an envelope. Bafflingly, many behaviors cited as implementing separation through cleansing are either pretend (participants hands are clean to begin with), or are even confounded with the opposite of separation, namely application (e.g., hand sanitizer) or outright contamination (e.g., burning incense). Clearly, learning is required here. Asking a concept to do such heavy lifting requires empirical and theoretical conscientiousness.

Empirically, the integration would benefit tremendously from evidence that the described experimental manipulations do in fact activate mental procedures of separation independently from the downstream consequences (i.e., manipulation checks). Those do not seem to be common in the cited studies.

Theoretically, paying more attention to how the concept of separation is developed ontogenetically will provide a more solid basis for the simultaneous universality and flexibility. The notions of grounding and simulation as used in the target article are based on Barsalou (Reference Barsalou1999). This seminal paper also theorized how perceptual symbols, the basis for simulations, develop in the first place. Barsalou focused on how these symbols are learned in a process of selective attention and subsequent storing of schematic sensory-motor states in long-term memory. That is presumably also the process assumed by L&S. Repeated experience of physical cleansing is schematized in a separation procedure concept. This concept is also subsequently evoked during mental dissociation (e.g., of the self from failure). The universality of that process might be explained by the fact that all humans have experience cleaning themselve, but that doesn't explain the rich variation on the theme.

However, Barsalou (Reference Barsalou1999) also noted that the learning process is likely to be influenced by genetic predispositions, for example through constraining the processing of space, objects, movement, and emotion. In his view, “a simulator is both a ‘rational’ and an ‘empirical’ system, reflecting intertwined genetic and experiential histories” (p. 586). Such intertwining of genetic and experiential determination is compatible with assumptions of dual inheritance approaches that argue that human biology and culture co-evolve and jointly determine behavior (Boyd, Reference Boyd2017; Boyd & Richerson, Reference Boyd and Richerson1985; Fiske, Reference Fiske2000; Henrich, Reference Henrich2016). The costs of learning are outweighed by the benefits of acquiring accumulated and locally adaptive knowledge.

Simultaneous universality of basic principles and variability of actual implementations also occurs in phenomena that are already studied from a dual inheritance approach, namely core cognition concepts in developmental psychology and emotion research.

In developmental psychology, the core cognition approach argues that infants' learning is guided by a stock of innate primitives that include conceptual representations (Carey, Reference Carey2009; Spelke, Reference Spelke2017). This includes basic cognitive concepts (e.g., magnitude and agency) and social concepts (e.g., authority and equality; Sheehy-Skeffington & Thomsen, Reference Sheehy-Skeffington and Thomsen2020; Thomsen, Frankenhuis, Ingold-Smith, & Carey, Reference Thomsen, Frankenhuis, Ingold-Smith and Carey2011): Although large and up imply power universally in general, exactly what needs to be large and up is learned from culture (Schubert, Reference Schubert2020). Interestingly, the approach assumes that these core concepts are combined (Spelke, Reference Spelke2017) or complemented by culturally driven learning (Carey, Reference Carey2009). The primitives are assumed to mostly remain active and constant throughout the lifespan, and can surface in adults when higher cognitive processes are taxed by mental load. This approach has concentrated on perception and cognition but could easily be extended to include behavioral output to accommodate procedures such as separation.

In emotion psychology, recent theorizing argues that emotions can be understood as combinations of innate functions that map appraisals onto motivations on the one hand, and culturally learned implementations on the other hand (Fiske, Reference Fiske2020; Fiske, Seibt, & Schubert, Reference Fiske, Seibt and Schubert2019). Both have to be learned in context, but their learning is directed by innate blueprints, explaining simultaneous universality and variation of such emotions (Zickfeld et al., Reference Zickfeld, Schubert, Seibt, Blomster, Arriaga, Basabe and Fiske2019).

In sum, parallel developments in various fields suggest that innate blueprints may underlie the acquisition of concepts that regulate social relations and guide emotional processes. Understanding procedures of separation may also benefit from incorporating dual inheritance. Here is how: First, acknowledging a dual inheritance of human behavior explains both the cultural universality of the general concept of separation and the incredible diversity of its triggers, ranging from washing-off to purifying through smoke. Second, it may well be that the involvement of the innate blueprint differs among the provided examples. It may be particularly prominent in the avoidance response provided by the disgust reactions, and much more incidental in purification by smoke. Third, dual inheritance theory may be key to understanding how the physical procedure of cleansing the body from visible contaminants can facilitate separating the self from associated mental concepts (e.g., a personality trait or a specific social group). As Fiske (Reference Fiske2000) pointed out, innate cognitive developmental proclivities would be most successful when they were generative rather than specialized to limited contexts. The grounded procedures of separation versus connection do not only occur in cleansing effects and the cited sympathetic magic effects of contagion. They also manifest in more complex scenarios such as tracking and establishing social alliances or communal relations through bodily markers (Fiske, Reference Fiske and Haslam2004; Kurzban, Tooby, & Cosmides, Reference Kurzban, Tooby and Cosmides2001). Their adaptive value is immense. Such applications of separation versus connection may be intermediate steps to more remote applications such as separating from an abstract concept like bad luck.

A dual inheritance approach to separation procedures would also generate new predictions about developmental trajectory, cultural differences, language dependence, working memory dependence, and malleability. Finally, considering the evolutionary basis of our phenomena along with their cultural evolution is crucial to establish a cumulative and coherent science, especially in fields such as social cognition that have largely used insulated theories that lack integration into larger frameworks (Muthukrishna & Henrich, Reference Muthukrishna and Henrich2019).