Coleman (1990, 177–80) implicitly includes the trusted’s incentives when he notes that a reciprocal trusting relationship, as in mutual trust in the iterated prisoner’s dilemma, is mutually reinforcing for each truster. Why? Because each person now has additional incentive to be trustworthy. I trust you because it is in your interest to do what I trust you to do so long as you want me to do what you trust me to do. If there is some residue beyond rational expectations in one-way trust, there is less role for that residue in this straight, likely self-interested, exchange.

Russell Hardin, Trust and Trustworthiness, loc. 1016