Re: Notes on 7/20 BLD draft

Michael Kifer wrote:
> 
>> Hassan Aït-Kaci wrote:
>>> Chris,
>>>
>>> Prenex form is a normal form for FOL, but not for Horn logic. In other 
>>> words, the prenex form of a Horn sentence may be non-Horn. 

I didn't think about this statement the first time I saw it.  Is this 
true?  can you show me a horn sentence that can't be expressed in prenex?

-Chris


-- 
Dr. Christopher A. Welty                    IBM Watson Research Center
+1.914.784.7055                             19 Skyline Dr.
cawelty@gmail.com                           Hawthorne, NY 10532
http://www.research.ibm.com/people/w/welty

Received on Friday, 27 July 2007 05:14:37 UTC