Can a computer fool you into thinking it is human?

Robert Epstein was looking for love. The year being 2006, he was looking online.

As he recounted in the journal Scientific American Mind, he began a promising email exchange with a pretty brunette in Russia.

Epstein was disappointed - he wanted more than a penfriend, let's be frank - but she was warm and friendly. Soon she confessed she was developing a crush on him.

"I have very special feelings about you. In the same way as the beautiful flower blossoming in mine soul... I only cannot explain... I shall wait your answer, holding my fingers have crossed..."

The correspondence blossomed, but it took a long while for him to notice that Ivana never really responded directly to his questions.

She would write about taking a walk in the park, having conversations with her mother, and repeat sweet nothings about how much she liked him.

Suspicious, he eventually sent Ivana a line of pure bang-on-the-keyboard gibberish. She responded with another email about her mother.

At last, Epstein realised the truth: Ivana was a chatbot.

What makes the story surprising is not that a Russian chatbot managed to trick a lonely middle-aged Californian man.

It is that the man who was tricked was one of the founders of the Loebner Prize, an annual test of artificial conversation in which computers try to fool humans into thinking that they, too, are human.

In other words, one of the world's top chatbot experts had spent two months trying to seduce a computer program.

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Each year, the Loebner Prize challenges chatbots to pass the Turing test, proposed in 1950 by the British mathematician, codebreaker, and computer pioneer Alan Turing.

In Turing's "imitation game", a judge would communicate through a teleprompter with a human and a computer. The computer's job was to imitate human conversation convincingly enough to persuade the judge.