Lojbab, in the midst of his several-message-long "Write in lojban, not about
it" screed (flame banked) did manage to clarify what is wrong with extension analysis vis a vis set of answers analysis: there are some answers which are not in the extension of the whatever minus Q-kau, as a function (the answers aren't the things that fit, but the whole expressions with them fitted in). As he noted, taking things makes no allowance for answers like (eliptically) "nothing," or {na'i}, which is always a possible answer. This also clarifies in what way {makau} is different from {ce'u}, for the latter does work in an extension-of sort of way. |