[FoRK] fear / greed

Joseph S. Barrera III joe at barrera.org
Fri Nov 5 08:46:50 PST 2004


Jeff Bone wrote:

>  Loosely defined, greed is "I want..." and fear is "I don't want..."
>
>  All the many other "emotions" are just variations on those two
>  themes...

This is starting to sound like Conceptual Dependency.

<http://www.cc.gatech.edu/computing/classes/cs3361_96_spring/Fall95/Notes/cd.html>

What the heck, I'm gonna fork the whole thing for future generations.

A POCKET GUIDE TO CD THEORY
Anthony G. Francis, Jr.
College of Computing
Georgia Institute of Technology
Atlanta, Georgia 30332-0280
centaur at cc.gatech.edu

1. Overview

Conceptual Dependency (CD) is a content theory of how to represent 
simple sentences. Since it was created by Roger Schank (1972), CD has 
gone through various incarnations - different sets of primitive actions, 
different types of states, and different theories of inference. We'll 
consider a cleaned-up, "canonical" CD theory which is fairly close to 
Schank's original conception but includes a cleaned-up theory of states, 
relations, and inferences.

At its core, CD is a theory of how to represent sentences. It has two 
basic axioms:

* For any two sentences that are identical in meaning, regardless of 
language, there should be only one representation.
* Any information in a sentence that is implicit must be made explicit 
in the representation of the meaning of that sentence."

 From these axioms, Schank built a theory based on a primary set of 
conceptualizations, which come in two kinds: active and stative.

* ACTIONS: (Active Conceptualizations):
An ACTION is performed by an ACTOR on some OBJECT with some DIRECTION.
* STATES (Stative Conceptualizations):
An OBJECT is in a STATE with some VALUE

Note - OBJECT and VALUE are not English words - they are conceptual 
cases which sometimes have counterintuitive meanings (for example, "John 
owns a book." could be represented:

(POSSESS (OBJECT JOHN) (VALUE BOOK))

Additionally, there are relationships between states, including static 
links which are used to define the meaning of sentences, and causal 
links which can be used to infer new CDs:

* RELATIONSHIPS: (Static Links):
A RELATIONSHIP is defined between a SOURCE CD and a TARGET CD.
* CAUSAL LINK (CD Inferences):
A CAUSAL LINK is defined between a SOURCE CD and a TARGET CD.

This breakdown does not precisely match original CD theory, but it 
explains the core concepts well enough for our purposes. Now, on to 
defining actual CDs…
2. ACTIONS

In order to represent identical meanings in an identical way, CD theory 
breaks actions down in two fashions: a core set of primitive acts which 
define the basic types of actions that occur, and a set of conceptual 
cases that add meaning to the basic action types.

While the canonical list of primitive acts has changed as CD theory has 
evolved, the original core set was:

* ATRANS, PTRANS, MTRANS
transfers (of posession, of physical objects, and of ideas)
* MOVE, PROPEL, GRASP
movement of body parts, application of force, grasping of objects
* INGEST, EXPEL
eating and anti-eating
* ATTEND, SPEAK
sensory attention, verbal output
* MBUILD
mental construction
* DO
anything not covered by the primitive 11 actions

However, these actions mean almost nothing by themselves. They must be 
augmented by conceptual cases that define how each action is played out 
with respect to the actor, the object of the action, the direction of 
the action, and so on …

* Action Core
ACTION ?action
ACTOR ?person
OBJECT ?anything
* Direction of Action
FROM ?location
TO ?location
* Modifiers of Action
INSTRUMENT ?conceptualization
TIME ?time

These are the "canonical" list of slots for an action; only MTRANS and 
MBUILD have different slots (an MOBJECT rather than an OBJECT). The 
remaining sections of this handout show how to build complex meanings 
out of these primitive actions, their conceptual cases, and an 
associated list of states.
2.1 ATRANS

ATRANS refers to a transfer of possession - the abstract transfer of 
possession from one person to another, as in a give or a buy. No 
physical transfer need take place; the transfer occurs purely on the 
plane of ownership.

Example: "John gave his house to his son."
(ATRANS (ACTOR JOHN)
(OBJECT HOUSE)
(FROM JOHN)
(TO SON)
(TIME PAST))

The primary state associated with ATRANS is POSSESS:

Example: "John's son has the house. "
(POSSESS (OBJECT HOUSE)
(VALUE SON))

(Technically, we could also specify a TIME for POSSESS, but we'll omit 
that for simplicity.)
2.2 PTRANS

PTRANS refers to a transfer of physical location - some object moves 
from place to place, as in a go or a move. Ownership need not 
transfer;possession - the abstract transfer of possession from one 
person to another. No physical transfer need take place; the transfer 
occurs purely on the plane of ownership.

Example: "Bob hands his wedding ring to the jeweler. "
(PTRANS (ACTOR BOB)
(OBJECT WEDDING_RING)
(FROM BOB)
(TO JEWELER)
(TIME PRESENT))

The primary state associated with PTRANS is AT-LOC.

Example: "The ring is at the jeweler's. "
(AT-LOC (OBJECT WEDDING_RING)
(VALUE JEWELER))

2.3 MTRANS

MTRANS refers to the transmission of an IDEA - some conceptualization is 
transmitted from one head to another (or within the same head). Tell, 
forget and remember can all be expressed with MTRANS. An idea is 
represented by an MOBJECT slot in CD, which is superficially like OBJECT 
except that it contains a whole concept as its value:

Example: "Bob told John that his wedding ring was at the jeweler's. "
(MTRANS (ACTOR BOB)
(MOBJECT (AT-LOC (OBJECT WEDDING_RING)
(VALUE JEWELER)))
(FROM BOB)
(TO JOHN)
(TIME PAST))

Frequently, we want to make a distinction between a person's memory (the 
LTM) and their central processor (CP) to allow us to discuss remembering 
and forgetting:

Example: "John forgot that Bob's wedding ring was at the jeweler's. "
(MTRANS (ACTOR JOHN)
(MOBJECT (AT-LOC (OBJECT WEDDING_RING)
(VALUE JEWELER)))
(FROM LTM)
(TO ?location)
(TIME PAST))
Example: "Bob remembered that his wedding ring was at the jeweler's. "
(MTRANS (ACTOR BOB)
(MOBJECT (AT-LOC (OBJECT WEDDING_RING)
(VALUE JEWELER)))
(FROM LTM)
(TO CP)
(TIME PAST))

2.4 MOVE

MOVE refers to the movement of a body part, not the movement of an 
object. Normally MOVE is instrumental to some other action (such as a 
kick or a throw), but sometimes it is used by itself, as in kiss, raise 
a hand, and scratch.

Example: "Bob raised his hand. "
(MOVE (ACTOR BOB)
(OBJECT HAND)
(FROM LOWERED)
(TO RAISED)
(TIME PAST))

The primary state associated with MOVE is POSITION.

Example: "Bob's hand is raised. "
(POSITION (OBJECT HAND)
(VALUE RAISED))

2.5 PROPEL

PROPEL refers to the application of force to an object. Normally PROPEL 
is instrumental to some other action, but sometimes it is used by 
itself. PROPEL verbs include pushing, pulling, throwing and kicking.

Example: "Bob threw the ball. "
(PROPEL (ACTOR BOB)
(OBJECT BALL)
(FROM BOB)
(TO ?location)
(TIME PAST))

The primary state associated with PROPEL is AT-LOC; generally the PROPEL 
will also be associated with a PTRANS that allows us to deduce the location.

Example: "Bob threw the ball to Bill."
(PTRANS (ACTOR BOB)
(OBJECT BALL)
(FROM BOB)
(TO BILL)
(TIME PAST)
(INSTRUMENT (PROPEL (ACTOR BOB)
(OBJECT BALL)
(FROM BOB)
(TO BILL)
(TIME PAST)))

2.6 GRASP

GRASP refers to the gripping of some object by a person. Normally GRASP 
is instrumental to some other action, but sometimes it is used by 
itself. Note that FROM and TO in general have little meaning with 
respect to GRASP. GRASP verbs include hold, grab, grasp and let go.

Example: "Bob picked up the ball. "
(GRASP (ACTOR BOB)
(OBJECT BALL))
(TIME PAST))

2.7 INGEST

INGEST refers to a person taking something inside his or her body: 
eating, drinking, breathing, etc.

Example: "Bob ate an apple. "
(INGEST (ACTOR BOB)
(OBJECT APPLE)
(FROM OUTSIDE-BOB)
(TO INSIDE-BOB)
(TIME PAST))

2.8 EXPEL

EXPEL refers to a person taking something outside his or her body: 
spitting, crying, sweating, etc.

Example: "Bob spat out the seeds. "
(EXPEL (ACTOR BOB)
(OBJECT APPLESEEDS)
(FROM INSIDE-BOB)
(TO OUTSIDE-BOB)
(TIME PAST))

2.10 ATTEND

ATTEND refers to a person attending or focusing a sense organ towards a 
stimulus - look, listen, feel, and so on.

Example: "Mary saw John. "
(ATTEND (ACTOR MARY)
(OBJECT EYE)
(FROM ?location)
(TO JOHN)
(TIME PAST))

2.9 SPEAK

SPEAK is an instrumental action that refers to the production of sound: 
say, play music, scream, and so on.

Example: "Mary screamed."
(SPEAK (ACTOR MARY)
(OBJECT SCREAM)
(TIME PAST))

2.11 MBUILD

MBUILD refers to the construction of a mental concept: realize, decide, 
imagine, conclude, etc. MBUILD frequently uses ATTEND as an instrumental 
action.

Example: "Mary saw John and realized he was in New York."
(MBUILD (ACTOR MARY)
(MOBJECT (AT-LOC (OBJECT JOHN)
(VALUE NY)))
(FROM ?no-location)
(TO CP)
(INSTRUMENT (ATTEND (ACTOR MARY)
(OBJECT EYE)
(FROM ?past-location)
(TO JOHN)
(TIME PAST)))
(TIME PAST))

2.12 DO

DO catches all the things that the first 11 primitive actions don't. 
It's also useful when we know something happened, but we don't precisely 
know what or how:

Example: "John fertilized the plants. "
(DO (ACTOR JOHN)
(OBJECT FERTILIZER)
(FROM ?location)
(TO PLANTS))

3. STATES

There is no set of "core states" in CD; states are an open set that can 
be continually added to. States share a common format, however: an 
OBJECT is in a STATE with some VALUE. Many states, such as HEALTH, have 
VALUES that range from -10 to 10; other states, such as AT-LOC, have 
discrete VALUES such as ATLANTA and NEW_YORK.

* State Definition
STATE ?state
OBJECT ?object
VALUE ?anything

Some prominent states include:

* HEALTH:
the physical well-being (or lack thereof) of a person, from perfect 
fitness (+10) to death (-10).

Example: "Mary is alive."
(HEALTH (OBJECT MARY)
(VALUE +10))

* MENTAL-STATE
the mental status of a person, from alert (+10) to unconscious (-10)

Example: "John is unconscious."
(MENTAL-STATE (OBJECT JOHN)
(VALUE -10))

* EMOTIONAL-STATE:
the emotional well-being (or lack thereof) of a person, from ecstatic 
(+10) to suicidal (-10):

Example: "John is depressed."
(EMOTIONAL-STATE (OBJECT JOHN)
(VALUE -5))

* AT-LOC
the physical location of an object.

Example: "John is in New York."
(AT-LOC (OBJECT JOHN)
(VALUE NEW_YORK))

* POSSESS
the state of ownership of an object.

Example: "John owns the book."
(POSSESS (OBJECT BOOK)
(VALUE JOHN))

* CONTROL
the state of control of an object.

Example: "Mr. Spock has the conn."
(CONTROL (OBJECT ENTERPRISE)
(VALUE SPOCK))

* FUNCTIONALITY
the physical status of some device

Example: "Voyager has been destroyed."
(FUNCTIONALITY (OBJECT VOYAGER)
(VALUE -10))

* KNOWS
whether some person has a concept in LTM

Example: "Bo knows nonlinear dynamics."
(KNOWS (OBJECT BO)
(VALUE NONLINEAR-DYNAMICS))

There are many other possible states; to represent a given sentence, you 
may need to invent a new state that captures the meaning. And many of 
these states would not be acceptable in a more detailed representation; 
when building an actual system, most designers go far beyond the simple 
STATE-OBJECT-VALUE triples of CD.
4. RELATIONSHIPS

We will distinguish two kinds of static relationships in CD: 
conceptual-level relations, which are CD conceptualizations in their own 
right, and case-level relations, in which a CD is attached by a 
conceptual case to another CD.

There are two primary flavors of conceptual-level relations, CAUSE and 
BI-CAUSE:

* CAUSE
One CD can be the "cause" of another. This is subtly different from the 
traditional causal inferences discussed in the next section; the primary 
difference is that CAUSE is used to define the basic meaning of a 
sentence explicitly, while causal types can be used to infer meanings 
from a sentence, even if those meanings are not explicitly stated.

Example: "Bill said something that made Mary listen."
(CAUSE
(SOURCE (SPEAK (ACTOR BILL)
(OBJECT WORDS)))
(TARGET (ATTEND (ACTOR MARY)
(OBJECT EAR)
(FROM ?location)
(TO BILL))))

* BI-CAUSE (sometimes written CAUSES)
two CDs can "mutually cause" each other. Verbs like "bought" and "sold" 
are prime examples of this; they are defined in terms of two primitive 
acts that occur more or less simultaneously

Example: "John bought a book from Mary."
(BI-CAUSE
(SOURCE (ATRANS (ACTOR MARY)
(OBJECT BOOK)
(FROM MARY)
(TO JOHN)
(TIME PAST)))
(TARGET (ATRANS (ACTOR JOHN)
(OBJECT MONEY)
(FROM JOHN)
(TO MARY)
(TIME PAST))))

There are two primary kinds of conceptual case relationships in CD, 
INSTRUMENT and MOBJECT:

* INSTRUMENT
a CD can be instrumental to performing another state.

Example: "Bob threw the ball to Bill."
(PTRANS (ACTOR BOB)
(OBJECT BALL)
(FROM BOB)
(TO BILL)
(TIME PAST)
(INSTRUMENT (PROPEL (ACTOR BOB)
(OBJECT BALL)
(FROM BOB)
(TO BILL)
(TIME PAST)))

* MOBJECT
a CD can be a mental object of an MBUILD or MTRANS

Example: "Mary saw John and realized he was in New York."
(MBUILD (ACTOR MARY)
(MOBJECT (AT-LOC (OBJECT JOHN)
(VALUE NY)))
(FROM ?no-location)
(TO CP)
(INSTRUMENT (ATTEND (ACTOR MARY)
(OBJECT EYE)
(FROM ?past-location)
(TO JOHN)
(TIME PAST)))
(TIME PAST))

5. CAUSAL RELATIONS

Unlike relationships, which are required to define the meaning of 
certain sentences but don't tell us much more about an action, a causal 
type allows us to infer certain things about existing sentences. (A 
causal type can also be used to define the meaning of a sentence, as 
we'll see in a second.) There are four primary types of causal relations:

* ENABLES
A STATE can ENABLE a particular ACTION. For example, the state of an 
ACTOR being AT-LOC a particular LOCATION will ENABLE the ACTOR to PTRANS 
FROM that LOCATION:

(RESULT (SOURCE (AT-LOC (OBJECT ?actor)
(VALUE ?location)))
(TARGET (PTRANS (OBJECT ?actor)
(OBJECT ?actor)
(FROM ?location)
(TO ?unknown))))

* RESULTS:
In turn, an ACTION can RESULT in a STATE. For example, an ACTOR 
PTRANSing TO some LOCATION will RESULT in the ACTOR being AT-LOC the 
LOCATION.

(RESULT (TARGET (PTRANS (OBJECT ?actor)
(OBJECT ?actor)
(FROM ?dont-care)
(TO ?location)))
(SOURCE (AT-LOC (OBJECT ?actor)
(VALUE ?location))))

* INITIATES
Whenever an event occurs or a state changes, an actor may become aware 
of it, and hence begin to think about it. This is an INITIATION causation.

Example: "When John came to New York, Mary realized he was there. "
(INITIATES (SOURCE (PTRANS (ACTOR JOHN)
(OBJECT JOHN)
(FROM ?location)
(TO NY)))
(TARGET (MBUILD (ACTOR MARY)
(MOBJECT (AT-LOC (OBJECT JOHN)
(VALUE NY)))
(FROM ?no-location)
(TO CP))))
Note this example is subtly different from our earlier example where 
Mary saw John; here we don't have that information, but we can still 
build the relationship.

* REASON
Whenever a thought occurs to an agent, an actor may act upon it. This is 
a REASON causation.

Example: "When Mary realized John had come to New York, she screamed."
(REASON (SOURCE (MBUILD (ACTOR MARY)
(MOBJECT (AT-LOC (OBJECT JOHN)
(VALUE NY)))
(FROM ?no-location)
(TO CP))))
(TARGET (SPEAK (ACTOR MARY)
(OBJECT SCREAM))))
Here Mary's mental realization prompts a perfectly reasonable physical 
action.

6. HOW MUCH DETAIL?

At many points during this discussion, we left out detail in sentences. 
States did not show time; actions did not always show instruments; and 
so on. Which is a pity, because many complex sentences really need five 
or six CD's to represent them properly. But that level of detail isn't 
necessary to illustrate the main points of CD, so we won't be that cruel.

For the assignments, unless otherwise indicated, you should not have to 
represent CD's to more than one level of nesting (a BI-CAUSE with two 
ATRANSes, a MBUILD with an MOBJECT or INSTRUMENT, and so on). Use only 
the predefined primitive ACTs and stick to the standard conceptual cases 
(ACTOR OBJECT MOBJECT TO FROM INSTRUMENT, and TIME), but feel free to 
create new states if absolutely necessary. Remember that CD states are 
represented by STATE-OBJECT-VALUE case triples; don't invent new cases 
for the states.

If you have any questions, please feel free to ask the TA's, or to check 
out one of the papers or books in the Additional Readings section for 
further information.
Further Reading

Schank, R. (1972). Conceptual dependency: A theory of natural language 
understanding. Cognitive Psychology 3 (4): 552-631.

Schank, R. and Abelson, R. (1972). Scripts, Plans, Goals, and 
Understanding. Lawrence Erlbaum Associates.

Schank, R. and Riesbeck, C.K. (1972). Inside Computer Understanding. 
Lawrence Erlbaum Associates.



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