Asked by: Nathaniel Hey, St Ouen, Jersey

In 2015, New York researchers used three NAO robots to address that question. Each was programmed to believe that two of them had had their voice deactivated. When asked which had been muted, one robot said it could hear itself so therefore must be the only one not silenced. The researchers have fallen short of saying that this robot is self-aware, instead saying it harbours a “logical and a mathematical correlate to self-consciousness”.

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