Dear PatC,
So is:
Giving1234
-
By Pat
-
Of Book23
-
To Mary1256
-
On 20090214Z-5
So much harder to cope with?
Regards
Matthew West
Information Junction
Tel: +44 560 302 3685
Mobile: +44 750 3385279
matthew.west@xxxxxxxxxxxxxxxxxxxxxxxxx
http://www.matthew-west.org.uk/
This email originates from Information Junction Ltd. Registered
in England and Wales No. 6632177.
Registered office: 2 Brookside, Meadow Way, Letchworth Garden
City, Hertfordshire, SG6 3JE.
From: ontolog-forum-bounces@xxxxxxxxxxxxxxxx
[mailto:ontolog-forum-bounces@xxxxxxxxxxxxxxxx] On Behalf Of Patrick
Cassidy
Sent: 11 February 2009 12:48
To: '[ontolog-forum] '
Subject: Re: [ontolog-forum] n-ary vs binary
I prefer the n-ary forms, because it allows one to say:
{PatC gave Book23 to Mary1256 on Date20090214Z-5}
This happens to be congenial to my
English-native-language way of reading, making comprehension faster than with a
set of binary relations.
Appropriate axioms can create the necessary and
sufficient relation of this assertion to each of the binary assertions, if they
are needed for some inference engine.
But I also feel that people should be able to use
any mode of _expression_ they want, and that there should be axioms that can
translate among the different modes.
PatC
Patrick Cassidy
MICRA, Inc.
908-561-3416
cell: 908-565-4053
cassidy@xxxxxxxxx
From: ontolog-forum-bounces@xxxxxxxxxxxxxxxx
[mailto:ontolog-forum-bounces@xxxxxxxxxxxxxxxx] On Behalf Of Pat Hayes
Sent: Wednesday, February 11, 2009 1:47 AM
To: maharri@xxxxxxxxx; [ontolog-forum]
Subject: Re: [ontolog-forum] n-ary vs binary
On Feb 10, 2009, at 4:45 PM, Mitch Harris
wrote:
PH, JS, et
al.:
Semantically, 'give' has three
participants. One or two may be
omitted in a grammatical English sentence
if they are obvious
from the context. But they exist,
whether or not the speaker
or listener knows who or what they are.
To get back to a single relation that is stipulated rather than follow the
many (interesting) lexical/semantic paths surrounding donation, let's stick
with 'give' having all three parameters.
Which begs the question. But let us
proceed.
Let me make what I think is the appropriate summary (yes many of the
following are arguable, and have already been argued, but there it is):
Given the ternary relation "Gives(A, B, C)" (which happens to
mean that A
gave B to C) we can easily encode it as three binary relations: assign a
unique x, then Gives1(x, A), Gives2(x, B), Gives3(x, C) is derivable from
the ternary relation and one can reverse the derivation.
Not quite. There is no 'assignment' and no
requirement of uniqueness. The translation into case/role binary form simply
refers to the existence of the giving action. Also, the translation is
usually stipulated so that the original ternary (or whatever) relation becomes
a predication establishing the event as having the appropriate verbal type, in
this case a giving. So one gets the pattern:
(exists (x)( Foo(x) &
FirsCaseName(x, A) & SecondCaseName(x, B) & ThirdCaseName(x, C) )
where the appropriate case/role names
depend on the particuiar verb, but often have 'agent' as the first one.
Converting everything to binary has its benefits: homogeneous
representation, most concepts are already binary (except maybe database
tables).
The most important advantages are (1) the
case/role names identify the various arguments by name, making it easier to
remember them (2) the second form allows partial information to be recorded and
used naturally, and allows for arbitrary extensions, and (3) it also puts the
actual event described by the verb phrase into the universe of discourse,
allowing other properties and relations to be asserted about it. Finally (4) it
means that a relatively simple notation (such as RDF graph syntax, ie a
labelled directed graph) can be used to represent what seem on the surface to
be much more complicated facts. This is probably the origin of the idea that
'most' relations are binary, which is actually much less obvious.
However, despite its simplicity, this equivalence/derivation is not well
known
It is very well known in AI/KR, ontology
engineering, formal logic and linguistics. Several widely used rule languages
are based on it.
, and even when known it is
counterintuitive to use (as humans usually
write these things).
On the contrary, for rendering the meanings
of simple English action sentences, it is actually in many ways more intuitive;
and it supports important 'obvious' entailments. For example, if John gave a
book to Mary, then it follows that Mary was given a book by John.
Could the n-ary/binary debate be settled by
allowing binary to be the
machine language and n-ary be the higher level human written language?
That is one way to proceed, but it ignores
the intuitive and human-engineering advantages of the case/role form, such as
its being easier to remember.
This whole topic is a storm in a teacup.
Real ontology engineering can all be done within binary languages such as RDF:
this has been known for decades. For some purposes, allowing higher adicity
relationships is advantageous, but even when they are possible, the classical
case/role system is still widely useful. It is easy, if a little tiresome, to
mentally translate back and forth between various surface conventions where
needed, and also to write preprocessors which present any logical form in
almost any way that a user feels comfortable with. Let everyone use their
favorite notation, and we can easily translate between them when
necessary.
------------------------------------------------------------
IHMC
(850)434 8903 or (650)494 3973
40 South Alcaniz St.
(850)202 4416 office
Pensacola
(850)202 4440
fax
FL 32502
(850)291
0667 mobile
|
_________________________________________________________________
Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/
Config Subscr: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/
Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx
Shared Files: http://ontolog.cim3.net/file/
Community Wiki: http://ontolog.cim3.net/wiki/
To join: http://ontolog.cim3.net/cgi-bin/wiki.pl?WikiHomePage#nid1J
To Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx (01)
|