In their paper, Lee and Schwarz identify grounded procedures of separation as a critical mechanism underlying the effects of cleansing behaviors. By physically distancing themselves from unwanted dirt and germs, people psychologically distance themselves from recent events. Cleansing manipulations and other forms of separation (or connection) that more directly engage sensorimotor capacities produce stronger effects.

In this paper, we leverage shared reality theory to provide a complementary perspective on cleansing behaviors and other forms of separation and connection. We propose that the extent to which particular behaviors are grounded in sensorimotor experience cannot fully account for the variance in their effects. For example, a given physical cleansing behavior – splashing water on a child's head – can have very different effects depending on the socially shared construal of the situation: the exact same cleansing behavior conducted by a priest during a baptism will be experienced as far more purifying than that conducted by a parent in the tub. The sensorimotor experience alone cannot explain the difference in the power of these identical cleansing behaviors. We propose that acts of cleansing and other acts of separation and connection have more powerful effects when they are grounded in shared practices – in a shared reality.

Humans engage in a variety of shared practices from a very young age. They learn to talk, eat, dress, and behave like others – they are taught “how we do things” (see Higgins, Reference Higgins2016 for a review). Many of these shared practices revolve specifically around cleansing. Children are taught particular bathing and toilet routines, depending on the culture they grow up in (Higgins, Reference Higgins2016; Rogoff, Reference Rogoff2003). Collective cleansing rituals abound, from preparation for the Chinese Lunar New Year to Thailand's Songkran festival, in which people cleanse themselves and their homes. Bathing is often performed communally in various countries (e.g., Japan, Morocco, and Sweden) and has been for much of history (e.g., Roman bathhouses). Even private rituals performed alone – tooth-brushing, washing clothes, shaving, and so on – are shared societal practices learned through interactions with others.

We argue that the power of these cleansing practices stems from more than just their physical movements and sensations. It also stems from shared reality – the perceived commonality with others of feelings, beliefs and concerns (inner states) about something (Echterhoff, Higgins, & Levine, Reference Echterhoff, Higgins and Levine2009; Hardin & Higgins, Reference Hardin, Higgins, Sorrentino and Higgins1996). Research has shown that the experience of shared reality predicts certainty (Rossignac-Milon, Bolger, Zee, Boothby, & Higgins, Reference Rossignac-Milon, Bolger, Zee, Boothby and Higgins2020); for example, conversation partners discussing ambiguous images who create a greater sense of shared reality feel more certain of what is truly going on in the images. We propose that cleansing behaviors rooted in shared practices feel truly clean, because people believe they clean in the right way (Higgins, Nakkawita, Rossignac-Milon, Pinelli, & Jun, Reference Higgins, Nakkawita, Rossignac-Milon, Pinelli and Jun2020). For example, people colloquially express the belief that their shared cultural practices surrounding toilet routines are cleaner than those of other countries (e.g., people raised to use toilet paper believe that toilet paper is superior to bidets, and vice versa).

The importance of social construction in the experience of cleansing is exemplified in the fact that many acts of cleansing do not involve physical acts of separation. For example, burning incense, which does not involve physical separation, is often considered to purify and cleanse the air. Thus, sensorimotor actions alone cannot fully explain the psychological effects of cleansing behaviors. The power of these behaviors also stems from the fact that people have a shared reality about them. In other words, it is the shared reality that makes baptism purifying and not the physical act of splashing water.

We propose that acts of cleansing that are grounded in a shared reality should produce stronger effects, such that cleansing behaviors should be more powerful if people see these behaviors as shared practices. For example, the most powerful types of cleansing behaviors should involve collective rituals simultaneously performed with others (e.g., collective bathing). Partaking in this cleansing ritual with others who share the same inner states about the cleansing should amplify its effects. Less powerful should be societally shared cleansing practices performed alone (e.g., bathing alone), and least powerful should be idiosyncratic cleansing behaviors performed alone that are not experienced as a shared practice.

We conceptualize sensorimotor grounding and shared reality not as additive, but as synergistic effects – each should amplify the effects of each other. For example, sensory experiences are amplified when experienced with others (Boothby, Clark, & Bargh, Reference Boothby, Clark and Bargh2014; Boothby, Smith, Clark, & Bargh, Reference Boothby, Smith, Clark and Bargh2016). Thus, engaging in a cleansing behavior with other people should make the sensorimotor experience even more engaging, further grounding the act of separation in the physical world. Similarly, engaging in a sensorimotor (vs. imaginary) practice should amplify the effects of shared reality: for example, research suggests that physical coordination (e.g., moving in synchrony) promotes social connection and shared cognition (Marsh, Richardson, & Schmidt, Reference Marsh, Richardson and Schmidt2009; Semin & Smith, Reference Semin and Smith2013). Thus, physically engaging in the shared practice together should amplify the effects of shared reality. In this way, shared reality should intensify the effects of sensorimotor behaviors, and vice versa. The synergy between these is exemplified by the fact that developmentally, children acquire shared practices during the same stage that they experience major sensorimotor development – in fact, one of the first acts of shared reality is protodeclarative pointing, which is a motor movement (Higgins, Reference Higgins2016).

In sum, we propose that cleansing behaviors and other acts of separation are procedures grounded not only in sensorimotor experience, but also in shared reality. We conceptualize these effects as synergistic, such that each amplifies the effects of the other. Given this synergism, physical acts of separation (and connection) performed together as a shared practice – acts grounded in both sensorimotor experience and shared reality – should be most potent.