Town religion is rules-based while tribal collective oaths express group loyalty

Evidence

In the towns, at least at the top, there is something which does more closely approximate to the Islam of the learned theologians: an exclusive unitarianism with a hidden deity, which proscribes mediation, and so theoretically recognizes no clergy, and which preaches an ethic of rules rather than of loyalty. It neither expresses the cohesion of groups, nor provides an idiom of treachery. The difference in style is well reflected in how you testify at court. The country folk testify in groups in collective oath. Under proper Muslim law, you testify as an individual. The collective oath of the tribesmen is really an expression of commitment to the group, an expression of a willingness to bear responsibility with it. — Diego Gambetta, Trust - Making and Breaking Cooperative…, 2007

Categorization

• XREF: Testifying as individual versus in collective oath is a direct analogue to trust resting on individual accountability versus group-embedded accountability — central to the blindness/Luhmann/Hardin synthesis.