Experimental work has revealed causal links between physical cleansing and various psychological variables. Empirically, how robust are they? Theoretically, how do they operate? Major prevailing accounts focus on morality or disgust, capturing a subset of cleansing effects, but cannot easily handle cleansing effects in non-moral, non-disgusting contexts. Building on grounded views on cognitive processes and known properties of mental procedures, we propose grounded procedures of separation as a proximate mechanism underlying cleansing effects. This account differs from prevailing accounts in terms of explanatory kind, interpretive parsimony, and predictive scope. Its unique and falsifiable predictions have received empirical support: Cleansing attenuates or eliminates otherwise observed influences of prior events (1) across domains and (2) across valences. (3) Cleansing manipulations produce stronger effects the more strongly they engage sensorimotor capacities. (4) Reversing the causal arrow, motivation for cleansing is triggered more readily by negative than positive entities. (5) Conceptually similar effects extend to other physical actions of separation. On the flipside, grounded procedures of connection are also observed. Together, separation and connection organize prior findings relevant to multiple perspectives (e.g., conceptual metaphor, sympathetic magic) and open up new questions. Their predictions are more generalizable than the specific mappings in conceptual metaphors, but more fine-grained than the broad assumptions of grounded cognition. This intermediate level of analysis sheds light on the interplay between mental and physical processes.

We propose that the metaphor of cleansing was a by-product of modernization processes. Based on cultural and historical evidence, we claim that the activation of cleansing metaphor triggered positive associations in times when separation was a positively regarded element of human culture and agriculture, but it should not exert the same effect in times when separation became culturally anachronistic.

Cleansing (separation) inductions reduce the impact of negative and positive reactions, whereas connection manipulations magnify them. We suggest that grounded procedures can produce these effects by affecting the perceived validity of thoughts. In accord with the self-validation theory, we also note the importance of considering how moderators, such as the meaning of the action and the timing of inductions, affect outcomes.

We link cleansing effects to contemporary cognitive theories via an account of event representation (intersecting object histories) that provides an explicit, neurally plausible mechanism for encoding objects (e.g., the self) and their associations (with other entities) across time. It explains separation as resulting from weakening associations between the self in the present and the self in the past.

Lee and Schwarz (L&S) suggest that separation is the grounded procedure underlying cleansing effects in different psychological domains. Here, we interpret L&S's account from a hierarchical view of cognition that considers the influence of physical properties and sensorimotor constraints on mental representations. This approach allows theoretical integration and generalization of L&S's account to the domain of formal quantitative reasoning.

We applaud the goals and execution of the target article, but note that individual differences do not receive much attention. This is a shortcoming because individual differences can play a vital role in theory testing. In our commentary, we describe programs of research of this type and also apply similar thinking to the mechanisms proposed in the target article.

Lee and Schwarz propose grounded procedures of separation as a domain-general mechanism underlying cleansing effects. One strong test of domain generality is to investigate the ontogenetic origins of a process. Here, we argue that the developmental evidence provides weak support for a domain-general grounded procedures account. Instead, it is likely that distinct separation procedures develop uniquely for different content domains.

According to Lee and Schwarz, the sensorimotor experience of cleansing involves separating one physical entity from another and grounds mental separation of one psychological entity from another. We propose that cleansing effects may result from symbolic cognition. Instead of viewing abstract meanings as emerging from concrete physical acts of cleansing, this physical act may be appended with pre-existing, symbolic meaning.

The hypothesis of grounded procedures of separation predicts accentuated effects in individuals with psychiatric disorders, for example, obsessive-compulsive disorders with washing compulsion. This could provide a vantage point for understanding cognitive processes related to specific disorders. However, fully exploring it requires updated experimental designs, including extensive control conditions, exclusion of alternative explanations, internal replications, and parametric variation to strengthen internal validity.

Using terror management theory and research findings, we expand the framework provided by Lee and Schwarz to highlight the potential link between separation and connection effects to existential, death-related concerns. Specifically, we address how death awareness may motivate separation and connection behaviors and how engaging in these behaviors may serve a protective terror management function.

The model presented by Lee and Schwarz provides a novel explanation for the elementary mechanisms of psychological cleansing. I argue that the model could be extended to account for complex instances of psychological cleansing where the grounded procedures are not isolated and the opposing motives of separation and connection are entangled in a strategic interplay.

Lee and Schwarz suggest grounded procedures of separation as a mechanism for embodied cleansing. We compare this process to other mechanisms in grounded cognition and suggest a broader conceptualization that allows integration into general cognitive models of social behavior. Specifically, separation will be understood as a mindset of completed avoidance resulting in high abstraction and openness to new experiences.

We propose that grounded procedures may help explain psychological variations across cultures. Here we offer a set of novel predictions based on the interplay between the social and physical ecology, chronic sensorimotor experience, and cultural norms.

Central to the account of grounded procedures is the premise that mental experiences are grounded in physical actions. We complement this account by incorporating frameworks in cultural psychology and developmental neuroscience, with new predictions. Through the examples of vicarious experiences and demerit transfer, we discuss why, and how, separation and connection may operate somewhat differently across cultures.

While Lee and Schwarz propose grounded procedures of separation as an explanation for physical cleansing in various domains (e.g., washing one's hands), we suggest that separation can also account for behavioral cleansing aimed at washing consciences and polishing reputations. We discuss this extension in terms of degrees of behavioral cleansing, motivations, and intentions behind cleansing, and social settings.

Are grounded procedures such as cleansing value-neutral main effects? Culture-as-situated-cognition theory suggests otherwise. Societies differ in how frequently they trigger membership and individualizing cultural mindsets and their linked mental-procedures – connecting and separating, respectively. Commonly triggered mindsets (and their linked mental-procedures) feel fluent. Fluency feels good. Cleansing can separate from but also connect to others in the form of membership-based rituals.

Lee and Schwarz made considerable theoretical advances in the psychology of cleansing by proposing that cleaning actions might serve as separation procedures between two psychological entities. Here, we propose that the effectiveness of the separation process may be modulated by the available amount of executive resources, and that separation may operate as a load-dependent resetting procedure.

The pattern of data underlying the successful replications of cleansing effects is improbable and most consistent with selective reporting. Moreover, the meta-analytic approach presented by Lee and Schwarz is likely to find an effect even if none existed. Absent more robust evidence, there is no need to develop a theoretical account of grounded procedures.

Lee and Schwarz interpret meta-analytic research and replication studies as providing evidence for the robustness of cleansing effects. We argue that the currently available evidence is unconvincing because (a) publication bias and the opportunistic use of researcher degrees of freedom appear to have inflated meta-analytic effect size estimates, and (b) preregistered replications failed to find any evidence of cleansing effects.

We propose that cleansing behaviors and other acts of separation or connection have more powerful effects when they are grounded in shared practices – in a shared reality. We conceptualize sensorimotor and shared reality effects as synergistic. Most potent should be physical behaviors performed collectively as a shared practice (e.g., communal bathing), grounded both in sensorimotor experience and in shared reality.