[Attempto] inverse names of relations

[Norbert E. Fuchs]

On 1 Sep 2011, at 10:00, Nagarjuna G wrote:

>  ... How to tell that the predicate "part of" and "consists of" are inverse to each other.


On Thu, Sep 1, 2011 at 2:25 PM, Norbert E. Fuchs <fuchs at ifi.uzh.ch> wrote:

> Are "part of" and "consists of" really inverse to each other? Though an engine is a part of a car the car does not consist of the engine.


On 1 Sep 2011, at 14:54, Nagarjuna G wrote:

> I assumed them to be.  Aren't they? 


As my car/engine example shows they aren't in general. To express the exact inverse in English you would have to say something like 

 If an engine is a part of a car then the car consists only of the engine.

ACE does not provide "only" but provides the special determiners "nobody but", "nothing but", and their variant "no ... but" that are used with bare plural noun phrases, bare mass noun phrases or proper names. Unfortunately these constructs do not allow for variables. Thus you cannot say

  If X is a part of Y then Y consists-of nothing but X.

You would need a more complex construct, for instance

  If X is a part of Y then if Y consists-of Z then Z is X.

Regards.

   --- nef