Re: An inconsistency or not?

You assert:

     card({...}) = 2

This is only true if John != Johnny, which we do not know. Your 
argument is invalid.

> It is my second reply. Consider the interpretation of the cardinality 
> restriction..
>
> {x $B":(B O | card({y $B":(B O$B"@(BLV : <x,y> $B":(B ER(p)}) = n}
>
> Substitute n = 1, x = Harry, p = hasFather into the interpretation..
>
> {Harry $B":(B O | card({y $B":(B O$B"@(BLV : <Harry,y> $B":(B ER(hasFather)}) = 1}
>
> Then..
>
> {y $B":(B {S(John),S(Johnny)} | card({John $B":(B O$B"@(BLV : <Harry,y> $B":(B 
> ER(hasFather)}) = 2 <> 1}
>
> Therefore the restriction (class axiom?), restriction(hasFather 
> cardinality(1)), is not satisified. Hence the collection of axioms is 
> not consistent.