Comment by John Searle

As to whether or not machines will be conscious, it is important to remember that we are machines. We are biological machines and we are conscious. I do not see any reason, in principle, why we could not build an artificial machine that was conscious, but we are unable to do that now because we do not know how the brain does it. The question, “Can you build an artificial machine that is conscious?” is just like the question “Can you build an artificial heart that pumps blood?” We know how to build artificial hearts because we know how the biological heart works. We do not know how to build an artificial brain because we do not know how the brain works. But assuming we knew how the brain worked, I see no obstacle in principle to building an artificial conscious machine. The important thing to see is that the human brain is a machine, a biological machine, and it produces consciousness by biological processes. We will not be able to do that artificially until we know how the brain does it and we can then duplicate the causal powers of the brain.