What does it mean to think? The power of being human‏

Artificial intelligence and humanity
Mechanical minds
The power of being human
The Economist, May 5th 2011 | from the print editionhttp://www.economist.com/node/18648170
 
The Most Human Human:
What Talking With Computers Teaches Us About What It Means To Be Alive.
by Brian Christian. Doubleday; 303 pages; $27.95. Viking; £18.99.
 
WHAT does it mean to think? The question has bothered philosophers for
millennia and computer scientists for decades. In 1950 Alan Turing,
who pioneered artificial intelligence, devised a test to determine how
well a machine can mimic mankind in an attempt to address whether
computers can think. He argued that if a computer could fool a person
into thinking that he was corresponding with another person, then it
would be impossible for that person to tell whether or not the
computer was thinking. Human judges have since been asked to
distinguish between two correspondents, one man, one machine, in a
competition held every year for the past two decades. Two years ago
Brian Christian landed the task of persuading these judges he was not
a computer. His account of the experience is entertaining and
informative.
 
 
Human beings like to think of themselves as possessing unique
capabilities such as being able to use tools, employ a language with
syntactic rules and process complex mathematical equations. Aristotle
argued that only people could reason. Yet the development of ever more
powerful and complex computers has chipped away at these claims: the
invention of logic gates, for example, allowed machines to make
deductions and when IBM’s Deep Blue computer defeated a chess world
champion, Garry Kasparov, in 1997, mankind seemed to lose ground to
machine.
 
Mr Christian is optimistic about humanity. He points out that
computers have areas in which they are competent and others in which
they are not. A computer can guide a missile, he notes, but not ride a
bicycle. People may be replaced by robots on farms, in factories, call
centres and laboratories but machines can only do work that lends
itself to automation. He describes the rise of artificial intelligence
as “maggot therapy: it consumes only those portions [of the job
market] that are no longer human, restoring us to health.”
 
Likewise the game played by Deep Blue serves to identify the
whereabouts of creativity in chess, he argues. A computer can win
through brute force by taking opening moves that lead to a game it has
already played out and won. The game becomes interesting only when it
treads on new territory and the computer is forced to recalculate in
response to an original placing of pieces rather than continue down a
well-worn path.
 
To prepare for his role in the Turing test held in 2009, in which
contestants compete for the Loebner prize for the most convincingly
human computer and the most convincingly human human, Mr Christian
analyses how computers fool people into thinking they are human and
what persuades people that they are indeed talking to a machine. He
recounts a tale told by Robert Epstein, who co-founded the prize with
Hugh Loebner. Mr Epstein was deceived into thinking he was exchanging
long letters online with a woman over a period of four months when he
was, in fact, talking to a chatbot. Mr Christian identifies what
distinguishes a computer from a real person: a machine that analyses
vast numbers of previous conversations to identify a suitable response
becomes inconsistent, for example, because its identity is actually
that of many individuals. A chatbot lacks motive: it has no particular
reason to say what it says and it speaks without really listening.
People produce timely answers, correctly if possible, whereas
computers produce correct answers, quickly if possible. Chatbots are
also extraordinarily tenacious: such a machine has nothing better to
do and it never gets bored.
 
No computer has yet fooled all those who judge the Loebner prize into
thinking that it was human and that the person it was being compared
with was a computer. But the contest has been close at times: in 2008
a chatbot deceived three of the 12 judges who interrogated it. The
2009 competition in which Mr Christian participated resulted in a
resounding victory for humanity—and for Mr Christian, who won the
“most human human” prize. Yet even if the computers were to triumph,
the prize would be awarded not to the machines but to the people who
created them.