Yes the problem is with what facts are asserted about Elvis. To see the people Cyc thinks are singers (like Frank Sinatra), you can ask (isa ?WHO Singer).
And while I don't really agree that famous music performers are usually also singers, I also don't agree with Cyc not dealing systematically with the important distinction between vocal performance and instrumental performance.
The bunch of facts asserted about MusicalPerformer are hurt by that failure (but then the thing they were focusing on was how to treat individuals and groups alike).
So the thing that the current facts support is knowing that singers are also musical performers (isa FrankSinatra MusicalPerformer).
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I'm new to Cyc and this is my first question related to reasoning.
I was surprised that Cyc cannot find a proof for this query:
(isa ElvisPresley-Musician Singer)
The reason is that ElvisPresley-Musician belongs to classes RockMusicPerformer and others, but there is no relation between these classes and Singer.
In reality, famous music performers are usually also singers. Is this just a missing fact in the Cyc factbase?
Even without this fact, is there a way to allow for looser reasoning, so that similar concepts like singer and musician are unified during inference?
Yes the problem is with what facts are asserted about Elvis. To see the people Cyc thinks are singers (like Frank Sinatra), you can ask (isa ?WHO Singer).
And while I don't really agree that famous music performers are usually also singers, I also don't agree with Cyc not dealing systematically with the important distinction between vocal performance and instrumental performance.
The bunch of facts asserted about MusicalPerformer are hurt by that failure (but then the thing they were focusing on was how to treat individuals and groups alike).
So the thing that the current facts support is knowing that singers are also musical performers (isa FrankSinatra MusicalPerformer).