Re: Less strong equivalences

Pat Hayes <phayes@ihmc.us> writes:
>> From your descriptions, I can't tell which one would best handle the
>> following situation:
>>
>> "Object 1 refers to exactly the same molecule (exemplar) as object 2 refers
>> to"
>
> That sure sounds like sameAs, applied to molecules. Why isn't sameAs good
> enough here? What goes wrong?

I can think of very few occasions when we want to talk about a molecule;
we need to talk about classes of molecules. We can consider this as
problematic even with a very simple example. 

Let's assume we have two databases with information about Carbon. Do we
use "sameAs" to describe the atoms that they are talking about? Maybe,
but what happens if one is talking about the structure of Carbon and
it's location in the periodic table, while the other is talking about
Carbon with the isotopic mix that we have in living organisms on earth?

In biology, we have the same problem. Is porcine insulin the same as
human insulin? Is "real" human insulin the same as recombinant
human insulin? Well, the answer to all of these is no, even though most
biologists will tell you that real and recombinant insulin are the same
because they have the same primary sequence; a medic will tell you
otherwise, because they have different effects. Why? Don't know. 

If you make the distinctions that you might need some of the time, all
of the time, then you are going to end up with a very complicated model.
Hence the evolutionary biologist says all the insulins are the same. The
medic says that they are different. And neither of them care about
different types of carbon (unless they are C14-dating). 

I don't think that there is a generic solution here which is not too
complicated to use. The only solution (which is too complicated) I can
think of is to do what we do when we have this problem in programming;
you use a pluggable notion of equality, by using some sort of comparitor
function or object. I don't think that this is an issue for OWL myself;
I think it's something we may need to build on top of OWL. 

Phil

Received on Thursday, 26 March 2009 12:17:18 UTC