 ‘Cassation’ is now an archaic word (though it survives in legal documents and other languages), but merely means “making null and void, canceling”. In effect, this theory holds that one who utters an insoluble proposition “isn’t saying anything”. The second of the texts just cited even gives a curious “ordinary language” argument, appealing to the rusticus (the man-in-the-street), who, if you were to say to him “What I am saying is false”, would reply “Nil dicis” (“You are saying nothing”).