Suppose, on the other hand, that I started life with such a charmed existence that I now am too optimistic about trusting others, so that I often overdo it and get burned. Because I am optimistic, I enter into many interactions, and I coincidentally, therefore, collect information for revising my estimates of the trustworthiness of others very quickly. My aggregate experience soon approaches the aggregate average, and I reach an optimal level of trust that pays off well in most of my interactions, more than enough to make up for the occasions when I mistakenly overrate the trustworthiness of another. Oddly, therefore, if parents are to err on one side or the other in instilling a belief that others are trustworthy, a simple learning account suggests that they should err on the side of instilling greater optimism in their children than they think is objectively warranted, at least with respect to modest issues of cooperation for which the losses at risk are not major.

QUESTION: Does this learning argument hold only for low-stakes cooperation, or does the risk calculus change for major losses? The author restricts the claim but the boundary case is worth probing.

Russell Hardin, Trust and Trustworthiness, loc. 554