Turing Test

What Is the Turing Test?

The Turing Test is a deceptively simple method of determining whether a machine can demonstrate human intelligence: If a machine can engage in a conversation with a human without being detected as a machine, it has demonstrated human intelligence.

The Turing Test was proposed in a paper published in 1950 by mathematician and computing pioneer Alan Turing. It has become a fundamental motivator in the theory and development of artificial Intelligence (AI).

Key Takeaways

  • The Turing Test judges the conversational skills of a bot.
  • According to the test, a computer program can think if its responses can fool a human into believing it, too, is human.
  • Not everyone accepts the validity of the Turing Test, but passing it remains a major challenge to developers of artificial intelligence.

How the Turing Test Works

Rapid advances in computing are now visible in many aspects of our lives. We have programs that translate one language to another in the blink of an eye; robots that clean an entire home in minutes; finance robots that create personalized retirement portfolios, and wearable devices that track our health and fitness levels.

All of these have become relatively mundane. At the forefront of disruptive technology now are the pioneers in the development of artificial intelligence.

'Can Computers Think?'

Alan Turing got there before them. This British mathematician developed some of the basic concepts of computer science while searching for a more efficient method of breaking coded German messages during World War II. After the war, he began thinking about artificial intelligence.

In his 1950 paper, Turing began by posing the question, “Can machines think?” He then proposed a test that is meant to help humans answer the question.

The test is conducted in an interrogation room run by a judge. The test subjects, a person and a computer program, are hidden from view. The judge has a conversation with both parties and attempts to identify which is the human and which is the computer, based on the quality of their conversation.

Turing concludes that if the judge can't tell the difference, the computer has succeeded in demonstrating human intelligence. That is, it can think.

The Turing Test Today

The Turing Test has its detractors, but it remains a measure of the success of artificial intelligence projects.

An updated version of the Turing Test has more than one human judge interrogating and chatting with both subjects. The project is considered a success if more than 30% of the judges, after five minutes of conversation, conclude that the computer is a human.

The Loebner Prize is an annual Turing Test competition that was launched in 1991 by Hugh Loebner, an American inventor and activist. Loebner created additional rules requiring the human and the computer program to have 25-minute conversations with each of four judges.

A chatbot named Eugene Goostman is accepted by some as the first to pass the Turing Test, in 2014.

The winner is the computer whose program receives the most votes and the highest ranking from the judges.

Chatting with Eugene

Alan Turing predicted that a machine would pass the Turing Test by 2000. He was close.

In 2014, Kevin Warwick of the University of Reading organized a Turing Test competition to mark the 60th anniversary of Alan Turing’s death. A computer chatbot called Eugene Goostman, who had the persona of a 13-year-old boy, passed the Turing Test in that event. He secured the votes of 33% of the judges who were convinced that he was human.

The vote is, not surprisingly, controversial. Not everybody accepts Eugene Goostman's achievement.

Critics of the Turing Test

Critics of the Turing Test argue that a computer can be built that has the ability to think, but not to have a mind of its own. They believe that the complexity of the human thought process cannot be coded.

Regardless of the differences in opinion, the Turing Test has arguably opened doors for more innovation in the technology sphere.

Article Sources
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  1. Stanford Encyclopedia of Philosophy. "The Turing Test."

  2. The National WWII Museum New Orleans. "Alan Turing and the Hidden Heroes of Bletchley Park: A Conversation With Sir John Dermot Turing."

  3. Turing, Alan. "Computing Machinery and Intelligence," Mind, vol. 49, 1950, pp. 433-460.

  4. Mohammed, Mohssen, et al. "Machine Learning: Algorithms and Applications." CRC Press, 2016.

  5. Shieber, Stuart M. "Lessons From a Restricted Turing Test.” Communications of the Association for Computing Machinery, vol. 37(6), 1994, pp. 70-78. 

  6. Marcus, Gary. "Am I Human?" Scientific American, 2017, pp. 60.

  7. Katrina LaCurts. "Criticisms of the Turing Test and Why You Should Ignore (Most of) Them," Page 2.

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