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NOTE
For more information regarding Alan Turing, the original inventor of the concept
for our model please refer to www.turing.org.uk.

Inventing…
The Turing Test

In 1950, Turing published an article entitled “Computing Machinery and
Intelligence,” in which he asked the question “Can a machine think?” In the same
article, he also posed another very interesting problem: if a machine can think,
how could we tell? So he tried and solved the problem by inventing an imitation
game, later called the “Turing Test for Intelligence,” to demonstrate that com-
puters in the future would be able to be programmed to emulate and rival
human intelligence. The game consisted in a human being and a computer that
were interrogated under specific conditions, so that the interrogator wouldn’t be
able to determine whom he was interacting with. The interrogation was per-
formed using a specific text-only communication protocol. Turing held that if the
questioner could not distinguish between the human and the machine within a
reasonable time, then there is no reason why we could not consider the either
the human or the machine as “intelligent.”
This test soon became the “Holy Grail” of the entire AI community, and is
still a fundamental reference point for many scientists and programmers world-
wide. In 1990, Hugh Loebner created a contest based on the Turing Test, with a
prize for the first computer whose results could be indistinguishable from a
human test subject, while every year a medal is awarded to the “most human”
computer. The contest is still open.
For more information regarding the Turing Test, please refer to
www.loebner.net/Prizef/loebner-prize.html

The Original Turing Machine

Examining each and every part of the original setup that Turing invented will help us to
understand thie device’s precise role in the entire structure.
The first and main part of the original Turing Machine consists of a tape of infinite
length, divided into cells. Each cell has just enough space for a single symbol to be
written.A head reads and writes on the tape, and can move one cell at a time, moving to
either the left or to the right.As you can see, the Turing Machine is a primitive machine
that can handle very basic operations such as moving and writing symbols. So, what’s the
interesting part?