 Now suppose we drop the first inequality of either \(a\) or \(b\) (but not both). A game that meets the resulting conditions might be termed a common knowledge PD. As long as each player knows that the other is rational and each knows the other's ordering of payoffs, we still feel the force of the dilemma. For suppose a holds. Then \(\bD\) is the dominant move for Row. Column, knowing that Row is rational, knows that Row will defect, and so, by the remaining inequality in \(b\), will defect himself. Similarly, if \(b\) holds Column will defect, and Row, realizing this, will defect herself. By \(c\), the resulting \((\bD,\bD)\) is again worse for both than \((\bC,\bC)\).