“But it does not stop there. Then there is the two of us talking, nay, the three of us, interacting as a whole that cannot be reduced merely to the three of us taken independently. A Holy Trinity thinking its little Trinitarian thoughts.
“And then a city, a country, or the entire world, all layers of the universal onion, and each of them conscious, some more and some less.”
“I see your point,” said J. “And yet consciousness seems to reside just once inside my head, your head, and Galileo’s head. Then Φ cannot be the answer.”
The onion, too, must be peeled with Occam’s razor, said Galileo. And when you do so, that will leave only its core— the core where integrated information reaches its maximum— the core that holds together while the rest peels off.
“So consciousness is not an onion, it is an onion’s core! This is quite some progress,” said Alturi. “But if you and I talk, what then? Don’t you and I, talking as we are doing now, form a larger core?”
Occam’s razor, once again, answered Galileo. You just said: “You and I, talking.” “You and I, talking” is much simpler, physically or informationally, than a would- be chimera mingling you and I. That monster has no holding power and would break down at its seams, you and me, where reality is carved into individual entities. Think not of monsters but of raindrops. Inside a drop of rain, molecules interact more strongly than with the air outside, and so a surface forms. The drop is a single entity and is contained within a border. When two droplets meet, either they bounce and remain separate, or they fuse and become a single, larger drop. There are no overlaps, nor drops within other drops. So it may be with consciousness: consciousness lives within a system where integrated information reaches a maximum, inside its own drop.
“So what you have understood is this,” said Alturi: “Experience cannot be reduced to anything less then it is. Impressive indeed.”
Ignoring Alturi, J. turned to Galileo. “If you are right, we should have a name for a system for which the information generated by the whole above its parts reaches a maximum, the onion core, the raindrop of consciousness. A complex, perhaps?”
Let’s call it so, said Galileo— a complex.
“So a complex is where consciousness lives,” said J. “There consciousness raises its house, erects its walls, and you are what’s inside, the rest of the world is what’s outside. The house of consciousness is one and cannot be shared: there is only one, only one owner, and it excludes all others.”
It was not clear whether Alturi liked this, but then he said: “I guess when you apply this analysis to the sensor of the camera, it will break down into complexes that are individual photodiodes, each of them distinguishing between just two states, on or off, but there will be no integrated entity— a complex— corresponding to the sensor. But when you analyze your brain, you will find inside it a set of nerve cells that form a large complex: one that can distinguish among a large repertoire of states in a way that its parts cannot; and one that does so maximally, more than any other set of nerve cells, more than the entire body, than any crowd of men, than the world itself.”
Precisely, said Galileo.
“Then I have something for you,” said Alturi, and handed Galileo some notes. The notes were from Frick and were full of diagrams representing parts of the brain. There was the cerebrum: without it, Copernicus had lost his consciousness forever. Galileo remembered when he and Frick had compared the cortex and thalamus to a great city. The diagram showed that a large expanse of the cerebral system formed a single complex of high Φ. This was because its elements, different groups of neurons, were specialized for different functions, and yet these specialists talked to each other— they were integrated within a single great complex that could distinguish among a vast number of different states, one for each experience.