the airstrip is not uninformative.
sent1: if the reckoner is a duck and/or it does service reckoner then the fact that the airstrip is not uninformative is right. sent2: The reckoner does service reckoner. sent3: the airstrip is not uninformative if the fact that the reckoner ducks is right. sent4: the reckoner does service reckoner.
sent4 -> int1: the fact that the reckoner is a duck or does service reckoner or both is not wrong.; int1 & sent1 -> hypothesis;
$hypothesis$ = the airstrip is not uninformative. ; $context$ = sent1: if the reckoner is a duck and/or it does service reckoner then the fact that the airstrip is not uninformative is right. sent2: The reckoner does service reckoner. sent3: the airstrip is not uninformative if the fact that the reckoner ducks is right. sent4: the reckoner does service reckoner. ; $proof$ = 
sent4 -> int1: the fact that the reckoner is a duck or does service reckoner or both is not wrong.; int1 & sent1 -> hypothesis; __PROVED__