Page 136 - DCAP506_ARTIFICIAL_INTELLIGENCE

Artificial Intelligence

Notes R
— recipient-donor.
I
— instrument e.g. eat with a spoon.

D
— destination e.g. going home.
 Double arrows () designate two-way links among the actor (PP) and action (ACT).

 The actions are constructed from the set of primitive acts.
 These can be customized by tense etc.
The use of tense and mood in illustrating events is tremendously significant and schank introduced
the following modifiers:

p
— past
f
— future
t
— transition
t
3
— start transition

t
f
— finished transition
k
— continuing
?
— interrogative
/

— negative
delta
— timeless
c
— conditional
the absence of any modifier points to the present tense.
So the past tense of the above example:

John gave Mary a book becomes:
from
p O R Mary
John ATRANS Book
to
John

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