Interest is one of the best and most useful of internal motivations. It leads us to and through much of the best that life has to offer. To suppress interest on occasions in which it leads us in directions we might consider wrong is to put ourselves at war with ourselves. In waging that war we are supported by social controls based in our own longer-term interest. A strong network of laws and conventions is needed to make any kind of behavior reliable if it is likely to conflict with powerful considerations of interest. All too often, we have neither law nor convention nor love to make us trustworthy, and it is often only the interest we have in maintaining particular relationships that makes it in our interest to be trustworthy.

XREF: Connects to intrinsic motivation research (Deci & Ryan self-determination theory) and the wellbeing cost of suppressing natural drives.

Russell Hardin, Trust and Trustworthiness, loc. 278