Cimpian & Salomon (C&S) present the inherence heuristic as a surprisingly simple and intuitive overarching cognitive process that accounts for a broad array of disparate research findings. C&S describe this process as addressing any feature that “can be said to characterize how an entity is constituted” (sect. 2.1.1, para. 1), and they define these features as salient, stable, accessible, intrinsic, internal, and nonobvious. Notably, the inherence heuristic does not address extrinsic factors, including historical information, and the justification for the exclusion of these factors is that they are not very salient or accessible. C&S use historical events and social conventions as two primary examples of extrinsic factors that may be reasonably excluded from consideration. However, we propose that the concept of ownership represents an extrinsic factor that poses two critical challenges to the present formulation of the inherence heuristic.

The first challenge is that historical information plays a critical role in identifying and tracking property (Gelman et al. Reference Gelman, Manczak and Noles2012). Ownership is abstract and nonobvious, like inherent features of entities, but, unlike historical events and social conventions, ownership is highly accessible and salient, even to very young children (Fasig Reference Fasig2000; Hay Reference Hay2006; Levine Reference Levine1983; Ross et al. Reference Ross, Tesla, Kenyon and Lollis1990; Saylor et al. Reference Saylor, Ganea and Vázquez2010). Whereas it may be reasonable to conclude that other extrinsic factors fail to be activated by the mental shotgun, ownership information has precisely the characteristics that should cause it to loom large in any narrative constructed by the storytelling component of the process. There are also thematic similarities between the output of intuitions about ownership and the explanations generated by the inherence heuristic. For instance, the output of both processes appears to be effortless despite resulting from a great deal of rapid, implicit cognitive processing.

The second challenge that ownership presents with respect to the inherence heuristic is that it provokes individuals to perceive the inherent, essencelike qualities of individuals in objects. At the most basic level, giving an individual a piece of property enhances that person's perception of its value (Beggan Reference Beggan1992; Gawronski et al. Reference Gawronski, Bodenhausen and Becker2007; Kahneman et al. Reference Kahneman, Knetsch and Thaler1990; Thaler Reference Thaler1980). In addition, the knowledge that an object has been in contact with a specific individual or special set of circumstances often results in intuitions that the object itself is contaminated or imbued with the essence of these individuals and events (Rozin & Nemeroff Reference Rozin, Nemeroff, Stigler, Shweder and Herdt1990). In this way, art may be appreciated because of its special, historical connection to an artist (Bullot & Rebar Reference Bullot and Rebar2013; Gelman et al. Reference Gelman, Meyer and Noles2013), and learning that a set of old, used golf clubs once belonged to JFK might dramatically inflate an individual's attraction to and valuation of the clubs, a response that can not be explained away completely by simple associations or market demands (Newman et al. Reference Newman, Diesendruck and Bloom2011). In this way, objects with no special status are granted authenticity, a nonobvious historical property that makes certain objects special. Critically, children as young as age 4 reason about authentic objects in an essentialist manner (Frazier & Gelman Reference Frazier and Gelman2009; Gelman et al. Reference Gelman, Frazier, Noles, Manczak and Stillwell2014). Because the essencelike effects of ownership appear early and persist into adulthood, it is unlikely that they are some later by-product of psychological essentialism. Thus, at least some element of historical information must be accounted for by any comprehensive explanation of psychological essentialism.

Historical information plays an important role in considerations of ownership and authenticity, a role that highlights several gray areas with respect to the inherence heuristic. First, is the separation between intrinsic and extrinsic information detailed by C&S meaningful? There are at least two effects of this dichotomy on the model: (1) a separation between internal features (e.g., DNA, insides, essences) and external features (e.g., conventions, surface details), and (2) a division between features that are salient and accessible and those that are not. These two elements travel together in the examples presented by C&S, but ownership is a case where the two might be split apart, unless one conceptualizes ownership in a very specific way (i.e., as an intrinsic feature that is historically, and therefore externally, defined – but whether this is possible is an empirical question).

Second, can historical information play a role in the output of the inherence heuristic? Historical information plays a critical role in defining property (Gelman et al. Reference Gelman, Manczak and Noles2012) and authentic objects (Frazier & Gelman Reference Frazier and Gelman2009). Ownership information is accessible and salient in exactly the way that other kinds of historical information, such as social conventions and historical events, are not. In its current formulation, the inherence heuristic states that the mental shotgun selects inherent features because they are salient and accessible, but there is no requirement that they be internal or intrinsic. Although it may be true that inherent features are overrepresented in human explanation, perhaps because they are salient and accessible, does the model need to be limited to inherent features?

Finally, can the inherence heuristic effectively serve as the foundation for psychological essentialism if it accounts only for essentialist thinking within a subset of domains? The inherence heuristic is a process that is proposed to explain broad patterns, and the relationship between individuals and property is consistent and systemic. More specifically, people treat property as though it is imbued with the essence of current and prior owners. Historical information is central to concepts of ownership, and historical path may be an important element of essentialism, especially with respect to artifacts (see Frazier & Gelman Reference Frazier and Gelman2009). However, in its current formulation, the inherence heuristic does not account for authenticity and other effects of ownership. Thus, the inherence heuristic appears to be well situated to address how we think about the intrinsic properties that underlie many human intuitions, but if this process is truly the foundation for psychological essentialism, then it needs to address historical information in some contexts.