Silas is a friendly-looking golden dog with floppy ears and a
pointy tail. If you hold out your hand, Silas will come up to you
wagging his tail and sit down, just like a real dog. He will even
bring you a ball and try to get you to play.

But Silas is not real. He is made from computer-generated shapes
and looks a little as though he escaped from a Disney cartoon.
Silas is one of a small but growing number of computer programs
that can mimic the behavior of friends, pets, and other objects of
human affection. Among them are Julia, with whom you can have long,
if strange, conversations; Phink, an unpredictable dolphinlike
creature; and Neuro-Baby, a digital infant who can analyze and
react appropriately to your moods.

Building ‘relationships’ with these digital creatures is, of
course, rather an unusual process. With Silas, for example, you
have to stand in front of a video camera looking at a projection
screen on which you see a picture of yourself, your room, and
Silas, added in by the computer program. Of course, these are all
virtual friends; robot friends with ‘real’ bodies are still a long
way off. For the more immediate future, the scientists and artists
who are creating digital companions want to explore what is needed
to make these computer-generated objects more friendly and engaging
to humans. Research is proving that we are often surprisingly
willing to read intelligence and intention into the creations of
computer programs.

‘The research goal behind Silas is to understand how you can
build an autonomous creature, like a dog, that seems to do the
right thing over time,’ says Bruce Blumberg, Silas’ creator and a
Ph.D. student at the Massachusetts Institute of Technology’s Media
Lab. People readily respond to Silas as though he were real,
creating explanations for his behavior the way they would with a
real dog. ‘From the user’s perspective,’ says Blumberg, ‘there’s a
sentient, intentional being there.’

The willingness of humans to see complex emotions in animals is
well known to ethologists. ‘People often ascribe feelings to a real
dog that are over and above what they really would admit, if
pushed, they believe the dog really feels,’ says June McNicholas, a
research fellow at the University of Warwick in England who has
worked extensively on the bond between humans and animals. ‘If
you’ve had a bad day at work,’ she says, ‘your dog may seem to
respond to this. And you’ll say to yourself, ‘He knows I had a bad
day at work.’ But you know that the dog doesn’t know you had a bad
day at work. All he knows is that you are moving and acting
differently than you usually do. And you know this.’

Reacting to Silas involves similar rationalizations. For
instance, Silas is interested in moving objects that are close to
him. If you reach out to pat him, your hand will be both moving and
close, and Silas will watch it. Silas doesn’t have any way of
knowing whether you’re touching him or not, but because he’s
watching your hand so intentlyit ‘appears’ that he is responding to
being patted. Users tend to explain his response in those terms
(‘I’m patting him, and he likes it’) and the explanation has
predictive value (whenever the user tries to pat the dog, the
response is the same) and so, in the user’s mind, Silas likes to be

People find Silas fascinating partly because they enjoy trying
to explain what he is doing. ‘If a creature behaves exactly the
same every time,’ says Blumberg, ‘that’s not very interesting. It
turns into a robot. On the other hand, if it’s totally
unpredictable, then it seems random, and it’s hard for the user to
develop an explanation with predictive value. The optimal place is
where there’s just enough surprise that you’re constantly coming up
with new explanations that make sense. I think that this is why we
like having ‘real’ pets.’

But there is a very long way to go before Silas can become

Bringing artificial pets into the outside world is far more
complex than creating images on a screen. This is why robotic pets
are many steps behind virtual ones. Skimer the robot illustrates
these constraints. Kino Coursey of Daxtron Laboratories in Fort
Worth, the developer of Skimer’s software, says that the robot can
identify objects visually and be trained to follow them around. To
do this, one trainer drags a chair, say, while the other uses a
joystick to instruct Skimer to move in pursuit of the chair.

Skimer builds a network of associations between the images it is
seeing and the commands it is receiving. For example, when the
chair moves out of the robot’s field of view, moving from right to
left, the trainer commands Skimer to turn to the left. Skimer
remembers the sequence of images and the commands associated with
them. Once Skimer has been trained, it will follow the left-turn
command whenever it sees a chair moving across its vision to the
left. The result, says Coursey, is that ‘you can drag a chair
around in front of it and he’ll follow it anywhere.’ But while
Skimer does this very well, it can’t do anything else. And it’s a
pretty hefty contraption, cobbled together from a child’s
six-wheeled riding toy, a camcorder, a computer, and 18 kilos of
batteries. Skimer, as Coursey puts it, ‘definitely belongs in the
back yard. You wouldn’t want him in the house.’

If Skimer could be made small and agile enough, could it replace
the family dog or cat? Erika Friedmann, a specialist in pets and
health in Brooklyn College’s health and nutritional science
department, acknowledges that the autonomy of artificial pets might
attract people the way real pets do. ‘People like pets because they
don’t have to make an effort to get positive feedback from another
being,’ she says. ‘Your pet makes some kind of acknowledgment that
you’re there and entices you to interact with it.’

But pets provide people with far more than unstructured
entertainment. They give us something to care for, something to
touch and fondle. They provide a reason for exercise, a feeling of
safety. McNicholas thinks that this is the fundamental weakness of
the artificial dog. ‘What kind of care could someone give a virtual
pet?’ she asks. ‘A lot of the closeness in a relationship with a
pet is based on how dependent the pet is on you. If an artificial
pet doesn’t depend on you, you don’t feel needed.

Excerpted with permission from New
(Sept. 16, 1995). Subscriptions: $140/yr.(52 issues)
from Virgin Mailing and Distribution, 10 Camptown Rd., Irvington,
NJ 07111.

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