Chater and Christiansen put forward an ambitious account of the origins of social order and cultural complexity that convincingly emphasizes bottom-up processes and directed innovations. They draw intriguing and bold implications, particularly the suggestion that capacities such as language, morality, and theory of mind may not require domain-specific mechanisms. Yet we found their framing unconvincing: The pressing question does not seem to be whether social tinkering occurs but what it entails and whether it is important.

In line with their central thesis, a large literature demonstrates that people construct, often incrementally, social orders. Myriad studies of self-organizing communities – including pirates (Leeson, Reference Leeson2007), prison gangs (Skarbek, Reference Skarbek2014), gold miners (McDowell, Reference McDowell2004), and small-scale societies regulating common-pool resources (Ostrom, Reference Ostrom1990) – document people deliberately assembling institutions, laying out and enforcing rules to coordinate behavior and promote positive-sum interactions (Hadfield & Weingast, Reference Hadfield and Weingast2012, Reference Hadfield and Weingast2013; Leeson, Reference Leeson2009). These systems are not just devised; they evolve as people adopt and refine rule systems that seem to best achieve goals like reducing exploitation (e.g., Berkes, Reference Berkes1986). Similar behaviors are observed in experimental settings, in which participants are placed in lawless environments and can be observed attempting to coordinate to create and enforce rules (Kimbrough, Smith, & Wilson, Reference Kimbrough, Smith and Wilson2010; Wilson et al., Reference Wilson, Jaworski, Schurter and Smyth2012).

The existence of social tinkering, it seems to us, is not especially controversial. Rather, we worry that the authors’ framing – social tinkering as a middle ground between, on the one hand, selection on fully random variation and, on the other, complete foresight – risks caricaturing positions and sidestepping the substantive questions animating the study of emergent social order. Few, if any, scholars seem to endorse either extreme. The central challenge seems less to establish that social tinkering occurs than understanding its structure and relative contribution.

Consider, for example, the simple trait landscape displayed in Figure 1, where “trait” refers to the form of a rule system and “payoff” describes the mean payoff enjoyed by individuals in the group. Suppose that a community without any norms or rules starts at point B and that tinkering moves them along the curve. Individuals encounter a problem – say, theft – and engage in the kind of directed innovation described by Chater and Christiansen. We can envision three possibilities for how such innovations ultimately give rise to the complex institutions underlying social order:

1. 1. Individuals are sufficiently competent at social engineering that they should be expected to arrive at locally (D) or even globally optimal institutions (E) within one or a couple rounds of tinkering.

2. 2. Individuals struggle to innovate optimal institutional arrangements – e. g., they are just as likely to generate arrangements that yield lower payoffs (A) as they are at producing incremental advantages (C) – yet, over longer time periods, they are adept enough at evaluating and tweaking rule systems that they can arrive at optima.

3. 3. Individuals struggle not only to innovate but also to evaluate and refine institutions reliably enough for within-group processes to discover optima in the absence of additional cultural evolutionary processes.

Figure 1.

A trait landscape.

Each of the above possibilities permits “tinkering”: Individuals contend with local challenges through instrumental tweaks to rule systems. Yet scholars seem split on which best describes the emergence of complex social institutions. One of us has argued that the first two possibilities are more likely (Singh, Reference Singh2022, Reference Singh2025; Singh, Wrangham, & Glowacki, Reference Singh, Wrangham and Glowacki2017), while others – including researchers who stress the role of cultural group selection (Boyd, Reference Boyd2018; Boyd & Richerson, Reference Boyd and Richerson2010) – seem to endorse the third. The different scenarios implicate contrasting cognitive capacities, contributing to disagreements over which psychological traits have been most critical in the evolution of our lineage. The first scenario – and, to some degree, the second – suggests critical roles for social simulation and coordinated problem-solving. The third, meanwhile, puts much greater emphasis on capacities that enable processes like cultural group selection, such as conformist social learning and normative punishment (Richerson et al., Reference Richerson, Baldini, Bell, Demps, Frost, Hillis, Mathew, Newton, Naar, Newson, Ross, Smaldino, Waring and Zefferman2016).

Chater and Christiansen’s account seems to align most closely with the second scenario – their dismissal of “deliberate design” seems to suggest they find the first possibility unlikely (contra, e. g., Leeson, Reference Leeson2009) – yet we could find little evidence in their article showing why this regime should prevail. Indeed, it’s possible that all three occur, and which predominates depends on the socioecological context and the nature of the norm or institution being tinkered with. For example, norms that distribute meat equally or according to effort might quickly develop through one- or few-shot coordinated tinkering, whereas, say, property rights on land might require longer processes of implementation, evaluation, and revision, as Ellickson (Reference Ellickson1993) found in his studies of early Jamestown, Plymouth, and Salt Lake City. As societies scale up, the efficacy of tinkering seems likely to decline. In larger and more complex systems, the consequences of institutional innovation appear harder to simulate, slower to observe, and more difficult to attribute. Under such conditions, processes beyond within-group tinkering, such as between-group competition, may play a larger role in refining institutions of coordination and cooperation.

Tinkering occurs; on this, we expect most will agree. The question remains, however, which features do the explanatory work and whether, in the absence of other cultural evolutionary processes, it alone can produce the institutions that scaffold cooperation.