In Part One we cast Turing and the influence of his notions of machine thinking and intelligence in the context of philosophy and cognition. In this part of the book we show what happened when his ideas were put into practice.

Early attempts at building social machines that could interact with humans using everyday language were explored through single-topic systems beginning with Eliza the imitative psychotherapist, and PARRY the paranoia simulation.

Although the ability to imitate human conversation, and the capacity to deceive human interrogators into believing they are interacting with another human, seems central to Turing's game, the whole performance of the test depends on the individual judgement of satisfactory responses by panels of interrogators. One person's idea of a satisfactory response to a question or statement might seem inadequate or even evasive in another person's estimation. Perhaps, as Turing felt, on the road to building a machine to take part and succeed in his imitation game, the journey would have enlightened humans a lot about themselves and how they ‘tick’.

While our research is ongoing, in the following chapters we present results from three public experiments investigating how difficult (or easy) it is to distinguish artificial conversation from natural discourse, what it means to be human in terms of using language, and whether machines are now able to answer questions in a satisfactory and sustained manner.

Between the first (2008) and second (2012) Turing test experiments that we conducted, IBM had achieved another momentous machine versus human moment. Following Deep Blue's success in a chess tournament in 1997, the first time a computer beat Garry Kasparov, chess grand master and former world champion, over a series, in 2011 IBM's Watson machine beat two human champions on an American general knowledge quiz show Jeopardy!.

Watson's team were invited to take part in the 2012 Turing test experiment but they declined. Disappointing as it was, their decision was not a surprise. IBM's latest supercomputer was not programmed to hold conversations; it was a reverse question–answer system sifting through massive amounts of data to find the most probable response (see Stephen Baker's book Final Jeopardy: Man vs. Machine and the Quest to Know Everything, 2011).