When I was 14, I came up with this thought experiment. Imagine it were possible to replace a single blood cell with an electronic equivalent that behaved transparently. Let’s say we start replacing cells in a being, we will call Jimmy, with equivalents one by one. Any any stage our Jimmy is still indistinguishable from the original. Jimmy still dreams and has an internal conscious experience.
Let’s say, as were replacing, we constructed a duplicate. When we are done we have two identical Jimmy androids. The common sense view in the 1960s would assert that one Jimmy was conscious and the duplicate was not, even though they were absolutely identical. How could you tell which was which? I find that absurd. It seems to me simpler to assume that brain activity in some way creates consciousness. It is not as though ghosts/souls possess bodies and the original Jimmy had one of these souls and the duplicate did not. Even if there were such things as souls, both bodies should be equally suitable homes for a soul. I so I fully expect complex machines to evolve consciousness.
SAL-9000: Will I dream?~ Roedy (1948-02-04 age:70)
Dr. Chandra: Of course, you will. All intelligent beings dream. Nobody knows why.