Mystery Number Five - Computational Linguistics and Talking Robots - page 108

terms as core values, the resulting inferences are applied to content proplets,
i.e., proplets without any variables.
For example, if the content Julia is looking for food is activated, the infer-
encefordownwardtraversalderivedin6.5.8maybeappliedtoitasfollows:

6.5.9 A PPLYING INFERENCE FOR DOWNWARD TRAVERSAL
antecedent

consequent

⎡
⎣

⎤
⎦

⎡
⎣

⎤
⎦

noun: food
fnc:

noun: α

β
prn: K

fnc: ( K)

prn: K+M

β

rule level down

where α {apple, pear, salad, steak}

matching and binding ⇑ ⇓

⎡
⎣

⎤
⎦

⎡
⎣

⎤
⎦

⎡
⎣

⎤
⎦

⎡
⎣

⎤
⎦

noun: Julia
fnc: look_for
prn: 18

verb: look_for
arg: Julia food
prn: 18

noun: food
fnc: look_for
prn: 18

noun: α
verb: (look_for 18)
prn: 25

content level

When the antecedent, consisting of a single pattern proplet with the core value
food , matches a corresponding proplet at the content level, the consequent de-
rives a new content containing the following disjunction 24 of several proplets
with core values corresponding to the elements of the restriction set of α :

6.5.10 O UTPUT DISJUNCTION OF THE DOWNWARD INFERENCE 6.5.8
⎡
⎣

⎤
⎦

⎡
⎣

⎤
⎦

⎡
⎣

⎤
⎦

⎡
⎣

⎤
⎦

noun: apple or
fnc: (look_for 18)
nc: pear
prn: 25

noun: pear
pc: apple
nc: salad
prn: 25

noun: salad
pc: pear
nc: steak
prn: 25

noun: steak
pc: salad
nc:
prn: 25

The proplets of the output disjunction are concatenated by the pc (for previous
conjunct) and nc (for next conjunct) features, and have the new prn value 25 .
They are related to the original proposition by the pointer address (look_for
18) serving as the fnc value of the first disjunct. The output disjunction may
be completed automatically into the new proposition Julia looks_for apple
or pear or salad or steak , represented as follows:

6.5.11 P ROPOSITION RESULTING FROM DOWNWARD INFERENCE 6.5.9
⎡
⎣

⎡
⎣

⎤
⎦

⎡
⎣

⎤
⎦

⎡
⎣

⎤
⎦

⎡
⎣

⎤
⎦

⎤
⎦

⎡
⎣

⎤
⎦

noun: apple or
fnc: (look_for 18)
nc: pear
prn: 25

noun: pear
pc: apple
nc: salad
prn: 25

noun: salad
pc: pear
nc: steak
prn: 25

noun: steak
pc: salad
nc:
prn: 25

noun: (Julia 18)
fnc: (look_for 18)
prn: 25

verb: (look_for 18)
arg: (Julia 18) apple or
prn: 25

This new proposition with the prn value 25 is derived from the input proposi-
tion with the prn value 18 shown at the content level of 6.5.9, and related to it
by pointer values.

24 See NLC'06, Chap. 8, for a detailed discussion of intrapropositional coordination such as conjunction
and disjunction.