ABSTRACT
The occasion for a rule's coming into being may often be looked upon as one in which costs either betoken the absence of social cooperation or stand in the way of extending it. A settled social rule exists if and only if there is a corresponding pattern of conformity and enforcement: It is a rule that people repay their debts. The harmonized views offer an important place for rules themselves as conditions favor some changes in rules and block others. In some connections it is important to distinguish between rules that treat the people subject to them as participants in collective actions and rules that treat the people subject to them as individual agents acting each on their own. The Dalhousie project has taken a special interest in changes of rules that pass through quandaries, where two or more rules to which attachmerit is approximately equal will combine to forbid at once all routines.
