Their combination, within a world of deep distrust, is itself a robust pillar of mafia business for, irrespective of values and cultural codes, the force of constraints and opportunities can bring about rational adaptation on the part of people living in proximity with mafioso networks, even if they are not related by kin or do not entertain strong beliefs about the social importance of adhering to the code of honour or that of silence.

Diego Gambetta, Trust - Making and Breaking…, loc. 2203