Mystery Number Four - Computational Linguistics and Talking Robots - page 84

At this point, the chain with partially 17 matching contents may be used by the
hungry agent as a model for regaining balance. All that is required is to replace
Mary by moi (transfer) and to derive new content with new prn and address
values as blueprints for action:

5.5.5 T RANSFER AND COMPLETION

rule level: β be hungry K cm β eat food K+1 pre

Word Bank: # #

β get food K+2 down β get α K+3 exec

# #

β α

at γ

locate K+4 exec

moi locate apple at cupboard 91

β take α K+5 exec

moi take (apple 91) 92

β α

K+6 up β eat food eat K+7

moi eat (apple 91) 93 moi eat food 94

The content propositions following the exec connective at the rule level, i.e.,
91-93 , are blueprints for action. 18 They are ready for realization, but the final
decision about whether or not they are actually passed on to the agent's action
components (cf. diagram 4.5.3, interface 6) is still open.

5.6 Subjunctive Transfer and Managing the Data Stream

The agent's decision of whether or not to realize a current blueprint for action
is implemented as a change of what is called the verbal mood in linguistics.
In English, the verbal moods are the indicative ,the subjunctive ,andthe im-
perative . In DBS, they are formally implemented as the ind, sbjv, and impv
values of the sem (antics) attribute in verb proplets (3.5.6).
Content derived by the agent's recognition is indicative. A blueprint derived
by inferencing, but not yet passed to the agent's action components, is sub-
junctive. Old content may be of any verbal mood and does not initiate any
action directly. However, activated old content may initiate the derivation of
new content by matching the initial antecedent (forward chaining) or a con-
sequent (backward chaining) of an inference chain. The propositions of this

17 If the agent were to assume (unnecessarily) that Mary must have been hungry (thus supplying content
all the way to the initial R inference), then this would correspond to an abductive inference in logic.
The point is that observing Mary locating, taking, and eating an apple is sufficient for the purpose at
hand.
18 If the propositions 91-93 have been executed successfully, proposition 94 completes the counter-
measure for regaining balance.