Until the End of Time: Mind, Matter, and Our Search for Meaning in an Evolving Universe

by Brian Greene

Tononi’s theory has a panpsychist leaning. Nothing in the proposal is intrinsically tied to a particular physical structure. Your experience of conscious awareness resides in a biological brain, but according to Tononi and his math, a sufficiently high value of ф, whether contained in neural synapses or neutron stars, would be consciously aware. For some, like computer scientist Scott Aaronson, this leaves the proposal open to what he deems a devastating attack. Aaronson’s calculations have shown that by cleverly linking together simple logic gates (the most basic of electronic switches), the resulting network can have values of ф as large as you like—on par with that of the human brain or even larger.28 According to the theory, the network of switches should be conscious. And that’s a conclusion Aaronson—and most people’s intuition—considers absurd. Tononi’s response? However strange and unfamiliar the conclusion, the network will be conscious. Now, you might think, He can’t really believe that. But consider your incredulity in context. How can it be that a three-pound clump of brain, when appropriately connected to a blood supply and network of nerves, has familiar conscious experience? That is the claim, based on all that science has so far revealed, that stretches credulity. Yet, because of your own inner world, it is a claim that you readily accept. If I then hand you something else, lacking body and brain, and suggest that it too is conscious, the stretch to accept t...