 Action-priority update (Baltag and Smets 2008b). Let \((M,w)\) be a pointed plausibility model and \((A,e)\) be a pointed plausibility action model. Let \(\models\) be a binary satisfaction relation defined between \((M,w)\) and formulas in the language \(\Lang\) of the precondition function \(\pre^A:E^A\to\Lang\) of the plausibility action model A. If \(M,w\models\pre^A(e)\), then the plausibility model   \[ M[A]=(W[A],{\geq}[A],V[A]) \]   is defined via the action-priority update operation \(M\mapsto M[A]\) given as follows: