 Many of these approaches use structures \(S = (\Omega, \Pi)\) where \(\Omega\) is again a set of classical models and \(\Pi\) is a mapping with the domain \(\wp(\Omega)\) (the set of subsets of \(\Omega\)) and an ordered co-domain \((D, &lt;)\). The exact nature of \((D, &lt;)\) depends on the given approach and we give some examples below. The basic common idea is to let \(\phi \nc^S \psi\) in case \(\Pi([\phi \wedge \psi])\) is preferable to \(\Pi([\phi \wedge \neg \psi])\) in view of \(&lt;\). The following table lists some proposals which we discuss some more below: 