Re: logic

On 25 Sep 2013, at 00:09, Yuk Hui <huiyuk@gmail.com> wrote:

> hi henry,
> 
> hope this finds you well. i need a bit of your help with logic, since you are the expert! what is the relation between description logic and Tarski's model logic? SW is based on description logic, how far does it go away from the FOL? i am interested in the question of systems, and the evolution of these systems... millions of thanks.
> 
> all the best,
> yuk 

Hi Yuk,

   Dean Allemang who wrote "Semantic Web for the Working Ontologist" will be much 
better placed to guide you with regard to your question above.

  As I understand from our philosophy of the Web Conferences the Semantic Web is
a variation on  Common Logic which Christopher Menzel presented in the Philosophy
of the Web seminars in Paris in 2012:

   http://web-and-philosophy.org/seminaire-philosophie-du-web/slides/

And Common Logic is just first order logic where you start with names as
the invariants, allowing one to change syntax as one wishes. But that maps
down to first order logic I think. So RDF and first order logic seem really close
to each other when you look at documents such as RDF Semantics.

Now OWL is a subset of this. It defines particular set theoretic relations it
seems to me, and establishes the consequences one can draw from them. 
It seems to be missing thoughts on indirect contexts which we now know to
be named graphs. 

But really the answer is that I don't know - I can just make educated guesses.
There are people on the Web Philosophy  mailing list who will be able to guide 
you much better.

Henry

Social Web Architect
http://bblfish.net/