Stuart Jeffries in The Guardian:
One summer’s day in 1976, the philosopher Daniel Dennett was driving along the Massachusetts turnpike when he had a disquieting thought. “If somehow my brain were moved into my chest cavity without destroying any connectivity, wouldn’t I still think my mind was right behind my eyes and between my ears?” Perhaps he could be decapitated and still be a professor of philosophy.
By the time he reached Poughkeepsie in New York state, Dennett recalls in his paradoxically engaging and annoying memoir, this thought experiment had become even wilder. What if his brain was kept alive in a vat connected to his body with radio links? Would his mind be in the vat? Bewitched by the possibility, he gave university talks in which he, like some philosophical PT Barnum, would toggle a switch on a metal box with a radio antenna and tried to convince his audience that he was being controlled by his remote brain.
The 1970s was the decade in which nutty professors such as Dennett regularly dreamed up thought experiments to explore the limits of what it is to be human.
More here.