that the envelope blinds but it is not a enate does not hold.
sent1: if something is glabellar it is a kind of a leasehold. sent2: something that is a blind and is not a enate is not a leasehold. sent3: something is a curassow and/or it is glabellar. sent4: if there is something such that it is a curassow and/or glabellar the envelope is glabellar.
sent2 -> int1: the envelope is not a leasehold if it is a blind and it is not a kind of a enate.; void -> assump1: Let's assume that the envelope is blind and is not a enate.; int1 & assump1 -> int2: the envelope is not a leasehold.; sent1 -> int3: the envelope is a leasehold if it is glabellar.; sent3 & sent4 -> int4: the envelope is glabellar.; int3 & int4 -> int5: the envelope is a leasehold.; int2 & int5 -> int6: this is contradiction.; [assump1] & int6 -> hypothesis;
$hypothesis$ = that the envelope blinds but it is not a enate does not hold. ; $context$ = sent1: if something is glabellar it is a kind of a leasehold. sent2: something that is a blind and is not a enate is not a leasehold. sent3: something is a curassow and/or it is glabellar. sent4: if there is something such that it is a curassow and/or glabellar the envelope is glabellar. ; $proof$ = 
sent2 -> int1: the envelope is not a leasehold if it is a blind and it is not a kind of a enate.; void -> assump1: Let's assume that the envelope is blind and is not a enate.; int1 & assump1 -> int2: the envelope is not a leasehold.; sent1 -> int3: the envelope is a leasehold if it is glabellar.; sent3 & sent4 -> int4: the envelope is glabellar.; int3 & int4 -> int5: the envelope is a leasehold.; int2 & int5 -> int6: this is contradiction.; [assump1] & int6 -> hypothesis; __PROVED__