View source for Description Logic

'''D'''escription '''L'''ogic (commonly abbreviated ''DL'') is a set of mathematical rules and expressions for describing an action or set of outcomes, based on a particular set of inputs, as defined by principles of mathematical.


== Specifications ==

* Prolog syntax: http://rigaux.org/language-study/syntax-across-languages-per-language/Prolog.html<ref>[[wikipedia: Prolog syntax and semantics]]</ref>
* IRIS Syntax: http://iris-reasoner.org/syntax
* POSL - Positional Slotted Language syntax: http://ruleml.org/submission/ruleml-shortation.html



== EXAMPLE ==

'''FACTS - Simpson Family tree'''<ref>The Simpson's Family tree: http://en.wikipedia.org/wiki/Simpson_family</ref>
<pre>
lastname('simpson').
lastname('bouvier').
man('homer').
woman('marge').
dog('santas little helper').
kitty('snowball II').
hasFather('homer','abe').
hasMother('homer','mona').
hasFather('marge','clancy').
hasMother('marge','jacqueline').
hasBrother('homer','herb').
hasSister('marge','patty').
hasSister('marge','selma').
hasSon('homer','bart').
hasSon('marge','bart').
hasAdoptedDaughter('selma','ling').
hasDaughter('homer','lisa').
hasDaughter('marge','lisa').
hasDaughter('homer','maggie').
hasDaughter('marge','maggie').
hasMaidenName('marge','bouvier').
hasPet('simpson','santas little helper').
hasPet('simpson','snowball II').
areMarried('homer','marge').
isUncle(?y,?z) :- hasBrother(?x,?y), hasSon(?x,?z).
isAunt(?y,?z) :- hasSister(?x,?y), hasDaughter(?x,?z).
isGrandfather(?y,?z) :- hasFather(?x,?y), hasSon(?x,?z).
isGrandmother(?y,?z) :- hasMother(?x,?y), hasDaughter(?x,?z).
isMale(?x) :- man(?x).
isFemale(?x) :- woman(?x).
isMale(?x) :- dog(?x).
isFemale(?x) :- bitch(?x).
isMale(?x) :- cat(?x).
isFemale(?x) :- kitty(?x).
isMale(?y) :- hasSon(?x,?y).
isFemale(?y) :- hasDaughter(?x,?y).
isMale(?y) :- hasAdoptedSon(?x,?y).
isFemale(?y) :- hasAdoptedDaughter(?x,?y).
isMale(?y) :- hasBrother(?x,?y).
isFemale(?y) :- hasSister(?x,?y).
isMale(?y) :- hasFather(?x,?y).
isFemale(?y) :- hasMother(?x,?y).
isFamily(?x) :- areMarried(?x,?y).
isFamily(?y) :- areMarried(?x,?y).
isFamily(?y) :- hasSon(?x,?y).
isFamily(?y) :- hasDaughter(?x,?y).
isExtendedFamily(?y) :- isFamily(?x,?y).
isExtendedFamily(?y) :- hasAdoptedSon(?x,?y).
isExtendedFamily(?y) :- hasAdoptedDaughter(?x,?y).
isExtendedFamily(?x) :- isGrandfather(?x,?y).
isExtendedFamily(?x) :- isGrandmother(?x,?y).
isExtendedFamily(?x) :- isAunt(?x,?y).
isExtendedFamily(?x) :- isUncle(?x,?y).
</pre>

'''EXAMPLE QUERY #1 - Which Simpsons are male? (infers that Bart, Homer, Abe, Herb, Santa's Little Helper are male from "son", ,"uncle", "grandfather" relationships, as well as "man" and "dog" fact)'''
<pre>
?-isMale(?x).
</pre>


'''EXAMPLE QUERY #2 - Who has a son? (Explicitly stated)'''
<pre>
?-hasSon(?x).
</pre>


'''EXAMPLE QUERY #3 - Who are in the Simpson family? (infered from son/daughter/marriage reciprocal relationships)'''
<pre>
?-isFamily(?x).
</pre>


'''EXAMPLE QUERY #4 - Who are the Simpson's pets? (Explicity stated)'''
<pre>
?-isPet('simpson').
</pre>


'''EXAMPLE QUERY #5 - Who are in the Simpson's "extended" family? (infered from family relationship and Pets, Grandparents, etc)'''
<pre>
?-isExtendedFamily(?x).
</pre>




== Tools ==

* '''IRIS Reasoner: http://iris-reasoner.org'''<ref>http://iris-reasoner.org/demo</ref>
* RACER: http://www.ifis.uni-luebeck.de/~moeller/racer/index.html
* DL-Learner: http://sourceforge.net/projects/dl-learner/
* Description Logic - Complexity of Reasoning (calculator/tool): http://www.cs.man.ac.uk/~ezolin/dl/

== Resources ==

* '''Description Logic - Knowledge Representation: http://dl.kr.org/'''


== Tutorials ==

* '''Making Linked Data Reasonable using Description Logics, Part 1 -- Can a ‘Separation of Concerns’ Lead to Better Slicing of the Pie?: http://www.mkbergman.com/?p=474'''
* '''Making Linked Data Reasonable using Description Logics, Part 2 -- Good Design is Based on the Work to be Done: http://www.mkbergman.com/?p=476'''
* Presentations on DL: http://www.cs.man.ac.uk/~horrocks/Slides/index.html


== External Links ==

* [[wikipedia: Description Logic]]
* [[wikipedia: Abox]]
* Back to the Future with Description Logics: http://www.mkbergman.com/?p=470
* Thinking ‘Inside the Box’ with Description Logics: http://www.mkbergman.com/?p=466
* Our Approach to Modeling, Fidelity, and KR: http://clarkparsia.com/weblog/2008/12/19/our-approach-to-modeling-fidelity-and-kr/

== References ==

<references />

== See Also ==

[[Rule Engine]] | [[Semantic Web]] | [[AI]] | [[Machine Learning]]