External trust becomes necessary for systems that must partner with outsiders.

Evidence

For many systems it can be vitally necessary that they are in a position to invest trust in their environment so that they can take part in relationships which are only to be achieved through mutual trust. The system members must then be able to display trust externally also. In the lower positions in modern large organizations, for example, internal relationships can be programmed in such detail that trust between members becomes virtually unnecessary because uncertainty in behaviour is overcome by other mechanisms. For some systems also, it is precisely in their internal relationships that substantial injections of distrust are needed for them to remain alert and capable of innovation, so as not to fall back into their customary pedestrian ways of relying on one another. — Niklas Luhmann, Trust and Power, 315

Categorization

• XREF: The claim that some systems need internal distrust to stay innovative complicates a simple ‘high trust is good’ reading — relevant to how Stevens’s unearned trust in Darlington yields stagnation rather than alertness.
• QUESTION: Worth exploring: what mechanisms ‘program’ internal relationships so thoroughly that mutual trust is unnecessary — and does Darlington Hall run on such programmed roles rather than trust?