This stimulating target article provides a bottom-up, cumulative model of human institution formation, demonstrating how complex cultural frameworks can develop piecemeal, in an emergent, locally goal-directed manner. The argument is compelling and, although other processes – epidemiological transmission (Cavalli-Sforza, Reference Cavalli-Sforza1986), top-down design (Pae, Reference Pae and Pae2024), and higher-level selection (Richerson et al., Reference Richerson, Baldini, Bell, Demps, Frost, Hillis, Mathew, Newton, Naar, Newson, Ross, Smaldino, Waring and Zefferman2016) – certainly contribute, C&C describe a genuine phenomenon. This will yield forthright discussion of how “social tinkering” either replicates or conflicts with extant models. Here, I instead extend the framework, considering self-expedient rhetorical argumentation and how self-interested social tinkering produces convergent institutions which differentially benefit dominant coalitions. First, some background.

Complex cultural institutions often (1) independently reoccur (Brown, Reference Brown2004), (2) provide functional solutions for context-specific problems (Blurton Jones, Reference Blurton Jones1982; Chapais, Reference Chapais2008), and (3) favor particular sub-populations over others (Fitouchi & Singh, Reference Fitouchi and Singh2022; Strassmann, Reference Strassmann1992; Singh et al., Reference Singh, Wrangham and Glowacki2017). Such phenomena are ubiquitous, and I provide several evocative, well-studied anthropological examples exploring gerontocratic/patriarchal power and its manifestation in economic and reproductive control.

Religious celibacy practices – where certain individuals, often younger siblings, are impelled/compelled to take lifelong chastity vows – re-occur across agrarian religions, and are maintained by strong, moral institutions promoting asceticism and self-denial (Qirko, Reference Qirko2002). Such institutions increase the inclusive fitness of patrilines by preventing inefficient subdivision of arable land (Micheletti et al., Reference Micheletti, Ge, Zhou, Chen, Zhang, Du and Mace2022) at partial expense of younger offspring. Primogeniture – where families bequeath assets to the eldest son – also reoccurs in agrarian societies. This similarly advantages first-born patrilines, is similarly policed through complex institutions, and similarly prevents inefficient subdivision of farmland (Hrdy & Judge, Reference Hrdy and Judge1993; Mace, Reference Mace1998; Shenk et al., Reference Shenk, Borgerhoff Mulder, Beise, Clark, Irons, Leonetti, Low, Bowles, Hertz, Bell and Piraino2010).

On the darker side of reproductive control, menstrual taboos and seclusion reoccur cross-culturally (Murdock & White, Reference Murdock and White1969). These institutions, often reinforced by married men, are a demonstrably effective anti-cuckoldry strategy (Strassmann et al., Reference Strassmann, Kurapati, Hug, Burke, Gillespie, Karafet and Hammer2012), forcing women to reveal reproductive status and the onset of pregnancy (Strassmann, Reference Strassmann1992). Again, these benefit certain individuals while regulating the reproductive freedom of others. Sex-biased (female) infidelity proscriptions are codified in several major religions (Strassmann, Reference Strassmann, Kurapati, Hug, Burke, Gillespie, Karafet and Hammer2012), even though female reproductive freedom, where prescribed, promotes increased child investment (Ellsworth et al., Reference Ellsworth, Bailey, Hill, Hurtado and Walker2014; Smith, Reference Smith1998) and reproductive success (Scelza, Reference Scelza2011). Cultural institutions promoting both male and female genital mutilation (Basedow, Reference Basedow1927; González-Timoneda et al., Reference González-Timoneda, Sánchez, González-Timoneda and Ros2022; Pounder, Reference Pounder1983) also reoccur, also leverage normative moral frameworks (Basedow, Reference Basedow1927; González-Timoneda, Reference González-Timoneda, Sánchez, González-Timoneda and Ros2022), and also facilitate reproductive control of women by men, or younger by older individuals (Cook et al., Reference Cook, Dickens and Fathalla2002; Paige & Paige, Reference Paige and Paige2021; Wilson, Reference Wilson2008).

These evocative examples are each (1) well-studied, (2) pertain to well-known, cross-culturally recurring structural inequalities, and (3) are regulated through complex normative, prescriptive legal, and moral frameworks; and there are many more examples (Singh et al., Reference Singh, Glowacki and Wrangham2016, Reference Singh, Wrangham and Glowacki2017). Though evolutionary anthropologists draw compelling theoretical and statistical connections between cultural institutions and their “functional” outcomes, the cultural processes which convergently design these institutions are under-theorized. C&Cs provide a ready explanation.

C&C describe how everyday conversations probe and negotiate moral representations of behavior, resulting in rapid emergent complex order, as new norms are invented, selected, and adjudicated. The target article stresses mutualism – collaborative coordination – facilitated by language and linguistic representations in the deliberate selection of local-level norms. Here, C&C emphasize improvement of rules/systems, framing even adversarial interactions as “bug fixing.” Indeed, cultural institutions, including those considered in my own hunter-gatherer research, frequently foster mutual benefit, cooperation, and equality (Stibbard-Hawkeset al., Reference Stibbard-Hawkes, Smith and Apicella2022; Stibbard-Hawkes, Reference Stibbard-Hawkes and Moreau2020; Smith et al., Reference Smith, Stibbard-Hawkes, Dimant, Mabulla, Bicchieri and Apicella2026; Thomson et al., Reference Thomson, Lew-Levy, von Rueden and Stibbard-Hawkes2025). However, the target article downplays inequalities of status and authority, conflicts of interest, and benefit asymmetries that shape local-level deliberations.

When finessing shared conventions, people face trade-offs between the benefits of shared heuristics (reducing decision-making costs and facilitating coordination) and their capacity to benefit some over others. Hence, even where Schelling equilibria provide general benefit, certain focal points more greatly benefit certain people. Where emergent local norms routinely result from intelligently directed innovations (Target Article, 5.2), natural selection will favor the motivational psychology and cognitive facilities for capitalizing upon opportunities to amplify ego-beneficial shared heuristics. Sighted watchmakers will habitually push cultural consensuses toward personal expediency.

Thus, if social tinkering is integral to institution formation, natural selection will foster a decision-making psychology characterized by (1) architecture to assess the implications of ad hoc, novel social rules for self-interest, (2) capacities for rhetorical self-expedient argumentation designed not (necessarily) for truth-telling but for compelling, motivated rhetoric, (3) counter-adaptations to detect/neutralize ego-non-beneficial rhetoric, and (4) coalitionary psychology for spontaneous cooperation in promoting norms providing coalition-level benefits.

This “lobbying” framing of social tinkering easily explains the origins of those institutions described above: Coalitions of high-status elders or land-holding men, driven by anxieties over infidelity or the intergenerational integrity of wealth, may collaboratively leverage influence and rhetorical faculties (Mercier & Sperber, Reference Mercier and Sperber2011), to build – piecemeal – legal, moral, and supernatural cultural grammars, justifying biased wealth transmission and/or reproductive control. Once these grammars have developed, self-interested individuals perpetuate them through appeals to tradition, identity, morality, and other prescriptive norm-policing.

Nor should we expect coalitionary tinkering to be unique to agrarian societies; and it occurs across hunter-gatherers (Keen, Reference Keen1978; Power, Reference Power2015; Stibbard-Hawkes & von Rueden, Reference Stibbard-Hawkes and von Rueden2025) and probably across time (Hayden, Reference Hayden2020), albeit with scant archaeological signature (Stibbard-Hawkes, Reference Stibbard-Hawkes2025).

The role of power coalitions in the “design” of normative institutions is well theorized in the social sciences. Influential Foucaultian theories of governmentality (Hunt & Wickham, Reference Hunt and Wickham1994), biopolitics (Davidson et al., Reference Davidson, Burchell and Foucault2008), and disciplinary power (Foucault, Reference Foucault1977), especially, assume power relations structure culture and knowledge. Analogous arguments from behavioral scientists include Trivers’ theory of adaptive self-deception (Wrangham, Reference Wrangham1999), Singh et al.’s (Reference Singh, Wrangham and Glowacki2017) self-interested enforcement theory (also see Singh, Reference Singh2025), and Hayden’s discussions of secret societies (Hayden, Reference Hayden2018, Reference Hayden2020). Mercier and Sperber’s (Reference Mercier and Sperber2011) argumentative theory of reason describes proximate-level psychological tools – conformation biases and motivated inference – allowing social tinkerers to lobby for self-expedient norms.

Though these works provide building blocks for a “lobbying theory” of cultural evolution, they are poorly integrated and, excepting Singh et al. (Reference Singh, Wrangham and Glowacki2017), aren’t well applied to cultural evolution. C&C’s concept of Social Tinkering completes the theoretical toolkit. This lobbying theory provides a powerful cultural-evolutionary framework for understand the etiology of unequal and coercive institutions. It may elucidate the origins of many “harmful cultural practices” (see Longman & Bradley, Reference Longman and Bradley2016). It would help us better understand the pernicious influence of corporate and coalational expediency in the non-meritocratic promotion of scientific ideas (Curtin, Reference Curtin1960; Hennessey, Reference Hennessey2020), and the biased selection of theory by policymakers (Furnas et al., Reference Furnas, LaPira and Wang2025). Most of all, though, it provides an exciting new analytical lens to explore the patterning of human culture; and while also a self-interested goal, I hope this is, on balance, a noble one.