Firstly, trust presupposes decision-making in a situation of risk, where the risk is attributable to the strategic behaviour of others or to the possibility that they will behave opportunistically. By opportunistic behaviour I have in mind not only such blatant forms as stealing and lying, but also more subtle techniques such as withholding information in an effort to confuse. As Dasgupta (this volume) has noted, the possibility of such behaviour is a necessary condition for the question of trust to arise. If all people are invariably honest, doing their best to fulfil their commitments, then there is no problem of trust as I have defined it.

DEFINE: Defines trust conditionally: it presumes risk from others' strategic or opportunistic behavior, including subtle forms like withholding information. XREF: Connects to the broader trust literature, including Dasgupta's work on risk and commitment, foundational in social capital theory. Builds on: "Trust requires voluntarily increasing one's vulnerability to another party."

Diego Gambetta, Trust - Making and Breaking…, loc. 2507