xblueredgreengreenFIGURE 111. "Find a block which is bigger than the one you are holding and put it into the
box." [Adapted from Terry Winograd, Understanding Natural Language, p.9.]- Eta Din: find a block which is taller than the one you are holding and
put it into the box. [Refer to Fig. 111.]
Dr. Tony Earrwig: SHRDLU has to figure out what is meant by "one" and
"it", as well as using deduction to decide which block it is holding.
SHRDLU: BY "IT", I ASSUME YOU MEAN THE BLOCK WHICH IS TALLER
THAN THE ONE I AM HOLDING.
Dr. Tony Earrwig: There were two possible referents for "it": the one selected,
and "the one you are holding". SHRDLU has heuristics for choosing
between them.
SHRDLU: OK.
Dr. Tony Earrwig: SHRDLU's hand has to set down the red block to
pick up the taller blue one. - Eta Din: what does the box contain?
SHRDLU: THE BLUE PYRAMID AND THE BLUE BLOCK. - Eta Din: what is the pyramid supported by?
Dr. Tony Earrwig: Earlier SHRDLU responded to "the pyramid" by saying "I
DON'T UNDERSTAND WHICH PYRAMID YOU MEAN." Now, it assumes that
you mean the one just mentioned.
SHRDLU: THE BOX. - Eta Din: how many blocks are not in the box?
SHRDLU, Toy of Man's Designing 587