 This case could be denoted by \(p'\), but it must be realized that \(p'\) will hardly ever be a definitive statement, since it is necessary to take into account the possibility that the proof of either \(p\) or \(\neg p\) might one day succeed. If one does not wish to risk having to retract what one has said, in the case \(p'\) one should not state anything at all. (Heyting 1930C: 960 [Mancosu 1998: 307])