Quantity of Experience: Brain-Duplication and Degrees of Consciousness

If a brain is duplicated so that there are two brains in identical states, are there then two numerically distinct phenomenal experiences or only one? There are two, I argue, and given computationalism, this has implications for what it is to implement a computation. I then consider what happens when a computation is implemented in a system that either uses unreliable components or possesses varying degrees of parallelism. I show that in some of these cases there can be, in a deep and intriguing sense, a fractional (non-integer) number of qualitatively identical phenomenal experiences. This, in turn, has implications for what lessons one should draw from neural replacement scenarios such as David Chalmer’s “Fading Qualia” thought experiment.

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Nick Bostrom Ph.D. is a philosopher at Oxford University, the Director of the Oxford Future of Humanity Institute, and the Chair of the Institute for Ethics and Emerging Technologies. He co-founded the World Transhumanist Association in 1998 and is a frequent spokesperson and commentator in the media.