Social information is immensely valuable. Yet we waste it. The information we get from observing other humans and from communicating with them is a cheap and reliable informational resource. It is considered the backbone of human cultural evolution. Theories and models focused on the evolution of social learning show the great adaptive benefits of evolving cognitive tools to process it. In spite of this, human adults in the experimental literature use social information quite inefficiently: they do not take it sufficiently into account. A comprehensive review of the literature on five experimental tasks documented 45 studies showing social information waste, and four studies showing social information being over-used. These studies cover ‘egocentric discounting’ phenomena as studied by social psychology, but also include experimental social learning studies. Social information waste means that human adults fail to give social information its optimal weight. Both proximal explanations and accounts derived from evolutionary theory leave crucial aspects of the phenomenon unaccounted for: egocentric discounting is a pervasive effect that no single unifying explanation fully captures. Cultural evolutionary theory’s insistence on the power and benefits of social influence is to be balanced against this phenomenon.
There is a discussion on “the producer-scrounger dilemma for information use” of potential interest:
Social information is only useful when others also gather information asocially. Cultural evolutionary models contain a possible explanation of egocentric discounting. Rogers’ influential model [81] showed that social learning may not provide any advantage over individual learning when the environment changes. The advantage of using social learning depends on the frequency of social learners in the population: if those are too numerous, social learning is useless. When there are mostly individual learners, copying is effective, because it saves the costs of individual exploration, and because the probability of copying a correct behaviour is high. However, when there are mostly social learners, the risk of copying an outdated behaviour increases and individual learners are advantaged. This means the advantages of social learning are inversely frequency-dependent: the more other people learn socially, the less efficient it is to learn from them. The same logic is reflected, on a smaller scale, in models of information cascades, where social learning can (with a small probability) become detrimental for an individual when too many other individuals resort to it. More generally, a broad range of models converge upon the view that social information use can be likened, in terms of evolutionary game theory, to a producer–scrounger dynamic [37,77,82]. At equilibrium, these games typically yield a mixed population of producers (individual learners) and scroungers (social learners), where neither type does better than the other [83,84]. Egocentric discounting might emerge from a producer–scrounger dilemma, as a response to the devaluation of social information which may occur when too many other agents rely on social learning.
Note that this seems to assume that people don’t use the “credence by my lights” vs. “credence all things considered”-distinction discussed in the comments.
Some evidence that people tend to underuse social information, suggesting they’re not by default epistemically modest:
There is a discussion on “the producer-scrounger dilemma for information use” of potential interest:
Note that this seems to assume that people don’t use the “credence by my lights” vs. “credence all things considered”-distinction discussed in the comments.