Similarly, (3) also seems plausible, and here too one can derive (3) provided that one is willing to accept the principle that only necessarily false propositions have a probability equal to zero. Here the reasoning will be that \(\Pr (P\mid G \amp k)\) can be equal to one only if the conjunction \(\negt P \amp G \amp k\) is necessarily false, which can be case only if either \(\negt P\) is necessarily false, or the conjunction \(G \amp k\) entails \(P\), neither of which is the case.