Date: Tue, 21 May 91 10:55:13 -0700
From: saka@cogsci.Berkeley.EDU
Subject: computer-generated stories
To: kandell@ccit.arizona.edu, lippard@ccit.arizona.edu, mayrudh@YALEVM.BITNET,
 patep@ccit.arizona.edu, saka@cogsci.Berkeley.EDU
Message-id: <9105211755.AA27744@cogsci.Berkeley.EDU>
X-Envelope-to: lippard, patep

	Schank reports on some of the stories that have been created
by a program called TALE-SPIN. Here is a story caught in a loop:

"Joe Bear was hungry. He asked Irving Bird where some honey was.
Irving refused to tell him, so Joe offered to bring him a worm
if he'd tell him where some honey was. Irving agreed. But Joe didn't
know where any worms were, so he asked Irving, who refused to say.
So Joe offered to bring him a worm if he'd tell him where a worm was.
Irving agreed. But Joe didn't know where any worms were, so he asked
Irving, who refused to say. So Joe offered to bring him a worm if
he'd tell him where a worm was..."

The next story shows that TALE-SPIN can handle reflexives syntactically but
not semantically:
'One day Henry Crow sat in his tree, holding a piece of cheese in his
mouth, when up came Bill Fox. Bill saw the cheese and was hungry. He
said, "Bill, I like your singing very much. Won't you please sing
for me?" Henry, flattered by this compliment, began to sing. The
cheese fell to the ground... Henry Crow saw the cheese on the ground,
and he became hungry, but he knew he owned the cheese. He felt pretty
honest with himself, so he decided not to trick himself into giving
the cheese. He wasn't trying to deceive himself, either, nor did
he feel competive with himself, but he remembered that he was also
in a position of dominance with himself, so he refused to give himself
the cheese, so he offered to bring himself a worm if he'd give himself
the cheese. That sounded okay, but he didn't know where any worms were.
So he said to himself, "Henry, do you know where any worms are?"...'

TALE-SPIN uses general-knowledge rules. Schank 
	gave the program a rule that if a character is in a river,
	he will want to get out because he will drown if he doesn't...
	If a character has legs it might be able to swim out, if it
	has wings it might be able to fly away, and... if a character
	has friends, he could ask them for help... a character falls
	because gravity moves that character...
Based on these rules, TALE-SPIN created this story:
"Henry Squirrel was thirsty. He walked over to the river bank where
his good friend Bill Bird was sitting. Henry slipped and fell in the
river. Gravity drowned."

Ref: Roger Schank with Peter Childers [1984] The Cognitive Computer,
Addison Wesley.