On the Foundations of Norm Psychology

Humans are remarkably cooperative. This large-scale cooperation—extending far beyond immediate kin—has allowed us to achieve a dominant position on Earth. But how is this cooperation sustained in the face of the apparent temptation to defect?

One crucial component is our reliance on norms that designate actions as required, permissible, or forbidden. Such norms are sometimes codified into law, but they need not be. In many cases, it’s in our rational self-interest to follow norms: violating them might expose us to punishment or make others less willing to cooperate with us in the future. But it seems we are often motivated to follow norms even when defection would be in our rational self-interest, e.g. helping a stranger or tipping at a restaurant you’ll never visit again.

How do we learn to follow norms and punish defectors? And how do we acquire intrinsic motivation to do so? Beginning with Sripada and Stich (2006), some researchers have proposed that we possess an innate, domain-specific norm psychology. This norm psychology picks up cues that norms guide some behaviors in our local cultural environment and infers what these norms are. It also provides us with the ability to detect norm violations, as well as intrinsic motivation to follow norms and punish violators. On this view, as norms or proto-norms began to arise in human communities, this new cultural environment provided intense genetic selection pressures favoring greater ability to learn and follow norms, in a case of gene-culture coevolution.

Heyes (2024) agrees that our ability to process and follow norms was critical to the emergence of large-scale cooperation, but disagrees with the further claim that this ability is due to an innate, domain-specific norm psychology. Instead, she thinks that the necessary innate features—such as greater intelligence, increased social tolerance and motivation, and attentional biases that from early infancy make us especially notice what other people do—are all domain-general and that the necessary domain-specific features are all culturally learned (“cognitive gadgets”) rather than genetically inherited. In this way, her criticism parallels her earlier criticism of the California school” (or Boyd-Richerson-Henrich school) of cultural evolution (Heyes 2018), which holds that many of our cultural learning biases have been genetically selected for.

Her criticism includes the following points:

  1. People often confuse common or frequent behavior with required or permissible behavior. So either we lack a specialized circuit for dealing with norms, or this circuit frequently malfunctions. (Though it’s not obvious to me why this would favor the view that the specialized circuits are culturally learned rather than innate.)
  2. In many models, a domain-general process like reinforcement learning appears sufficient for learning norms.
  3. Subsequent studies have shown that our intrinsic motivation to follow norms is not as strong as previously thought. While people may be inclined to engage in costly punishment of defectors in laboratory settings, they are less likely to do so in the wild, where they are not under observation by experimenters. (Though again, it’s not obvious to me why this would favor a cognitive gadgets” account. Perhaps the idea is that a genetically inherited norm psychology would not be rigid enough to accommodate this flexibility?)

While I initially came to cultural evolution via the Henrich-Boyd-Richerson approach, I’ve found some of Heyes’ criticism compelling. But what is at stake in this debate? One interesting possibility is that if Heyes is right, it should be easier to generate cooperative, norm-following behavior in AI agents. After all, creating the appropriate innate, domain-specific modules from scratch might be difficult, as it seems to require major revisions to the overall architecture. By contrast, if norm psychology is culturally learned, it might suffice to expose agents to appropriate stimulus and feedback.

March 25, 2024