Unlike classical panpsychism, not all physical objects have a &PHgr; that is different from zero. Only integrated systems do. A bunch of disconnected neurons in a dish, a heap of sand, a galaxy of stars or a black hole—none of them are integrated. They have no consciousness. They do not have mental properties.
Last, IIT does not discriminate between squishy brains inside skulls and silicon circuits encased in titanium. Provided that the causal relations among the circuit elements, transistors and other logic gates give rise to integrated information, the system will feel like something. Consider humankind's largest and most complex artifact, the Internet. It consists of billions of computers linked together using optical fibers and copper cables that rapidly instantiate specific connections using ultrafast communication protocols. Each of these processors in turn is made out of a few billion transistors. Taken as a whole, the Internet has perhaps 10
When I talk and write about panpsychism, I often encounter blank stares of incomprehension. Such a belief violates people's strongly held intuition that sentience is something only humans and a few closely related species possess. Yet our intuition also fails when we are first told as kids that a whale is not a fish but a mammal or that people on the other side of the planet do not fall off because they are upside down. Panpsychism is an elegant explanation for the most basic of all brute facts I encounter every morning on awakening: there is subjective experience. Tononi's theory offers a scientific, constructive, predictive and mathematically precise form of panpsychism for the 21st century. It is a gigantic step in the final resolution of the ancient mind-body problem.
Panpsychism in the West. David Skrbina. MIT Press, 2005.
Consciousness: Confessions of a Romantic Reductionist. Christof Koch. MIT Press, 2012.
Integrated Information Theory of Consciousness: An Updated Account. Giulio Tononi in Archives Italiennes de Biologie, Vol. 150, No. 4, pages 293–329; December 2012.