Faking it

Joseph Weizenbaum’s classic work on ELIZA stands as possibly the oldest and best-known attempt to imitate human-like intelligence in a computer system. ELIZA plays the role of a Rogerian psychologist, taking the user’s thoughts and reflecting them back as seemingly insightful questions. Take, for example, the following excerpt from a transcript in which ELIZA’s response is indicated by capital letters:

Men are all alike.
IN WHAT WAY?
They’re always bugging us about something or other.
CAN YOU THINK OF A SPECIFIC EXAMPLE?
Well, my boyfriend made me come here.
YOUR BOYFRIEND MADE YOU COME HERE?
He says I’m depressed much of the time.
I AM SORRY TO HEAR YOU ARE DEPRESSED.
It’s true. I am unhappy.
DO YOU THINK COMING HERE WILL HELP YOU NOT TO BE UNHAPPY?
I need some help, that much seems certain.
WHAT WOULD IT MEAN TO YOU IF YOU GOT SOME HELP?
Perhaps I could learn to get along with my mother.
TELL ME MORE ABOUT YOUR FAMILY.
My mother takes care of me.
WHO ELSE IN YOUR FAMILY TAKES CARE OF YOU?
My father.
YOUR FATHER?
You are like my father in some ways.
WHAT RESEMBLANCE DO YOU SEE?
You are not very aggressive but I think you don’t want me to notice that.
WHAT MAKES YOU THINK I AM NOT VERY AGGRESSIVE?
You don’t argue with me.
WHY DO YOU THINK I DON’T ARGUE WITH YOU?

The system has a compelling appearance of deep intelligence but it is entirely faked by simple word substitutions. For example, in the last exchange, the system has matched You and me against a template and replaced them with the patterns WHY DO YOU THINK I and YOU respectively. Almost all of this dialog has been generated by such substitutions (i.e., my for your; my mother for who else in your family; I need for what would it mean to you if you got) and generic questions (e.g., in what way). Its apparent intelligence stems from the accumulated effect of a large collection of substitution rules and the human tendency to attribute intelligence and find explanations in any complex behaviors.

Modern day ‘chatter-bots’, conversational agents and virtual humans are more sophisticated realizations of the same basic mechanism, finding application in customer service, recruiting and even the criminal world .