[Attempto] Doubt in RACE

[Norbert E. Fuchs]

On 19 Apr 2012, at 19:01 , George Herson wrote:

>> There is a city X1.
>> Delhi is the city X1.
>> The city X1 is located in India.
>> 
>> 
>> indicating that your sentence "It is located in India." is interpreted as "The city is located in India.", and not as you assumed as "Delhi is located in India.". 
> 
> Why doesn't conclusion "Delhi is the city X1" mean that "the city X1" and "Delhi" are the same thing to the reasoner?

George

First, you probably didn't mean the word "conclusion" since the paraphrased sentences are part of the axioms.

Second, in our case "the city X1" is an anaphoric reference to "a city". ACE does not know definite descriptors as "the king of France".

Third, getting to your point, the Attempto group discussed at length whether the identity 

Delhi is a city. |- A city is Delhi.

should be allowed. For some time, RACE allowed it and the current version doesn't. The respective internal axioms are commented out.

Regards.

   --- nef