by Christof Koch
December 19, 2013
from ScientificAmerican Website
Panpsychism, the ancient doctrine
that consciousness is universal,
offers some lessons in how to think
about subjective experience today
He, as with all the other, much larger dogs that subsequently accompanied me through life, showed plenty of affection, curiosity, playfulness, aggression, anger, shame and fear. Yet my church teaches that whereas animals, as God's creatures, ought to be treated well, they do not possess an immortal soul. Only humans do.
Even as a child, to me this belief felt intuitively wrong. These gorgeous creatures had feelings, just like I did.
Why deny them? Why would God resurrect people but not dogs?
This core Christian belief in human
did not make any sense to me. Whatever consciousness and
mind are and no matter how they relate to the brain and the rest of
the body, I felt that the same principle must hold for people and
dogs and, by extension, for other animals as well.
Indeed, when I spent a week with His Holiness the Dalai Lama earlier in 2013 [see "The Brain of Buddha," Consciousness Redux; Scientific American Mind, July/August 2013], I noted how often he talked about the need to reduce the suffering of "all living beings" and not just "all people."
My readings in philosophy brought me to panpsychism, the view that mind (psyche) is found everywhere (pan).
Panpsychism is one of the oldest of all philosophical doctrines extant and was put forth by the ancient Greeks, in particular Thales of Miletus and Plato.
Philosopher Baruch Spinoza and mathematician and universal genius Gottfried Wilhelm Leibniz, who laid down the intellectual foundations for the Age of Enlightenment, argued for panpsychism, as did philosopher Arthur Schopenhauer, father of American psychology William James, and Jesuit paleontologist Teilhard de Chardin.
It declined in popularity with the rise
of positivism in the 20th century.
There are three broad reasons why
panpsychism is appealing to the modern mind.
Physiological measures of pain confirm this inference - injured dogs, just like people, experience an elevated heart rate and blood pressure and release stress hormones into their bloodstream.
I'm not saying that a dog's pain is
exactly like human pain, but dogs - as well as other animals - not
only react to noxious stimuli but also consciously experience pain.
For instance, bees are capable of recognizing specific faces from photographs, can communicate the location and quality of food sources to their sisters via the waggle dance, and can navigate complex mazes with the help of cues they store in short-term memory (for instance, "after arriving at a fork, take the exit marked by the color at the entrance").
Bees can fly several kilometers and return to their hive, a remarkable navigational performance. And a scent blown into the hive can trigger a return to the site where the bees previously encountered this odor.
This type of associative memory was
famously described by Marcel Proust in
└ la Recherche du Temps
Perdu. Other animals can recognize themselves, know
when their conspecifics observe them, and can lie and cheat.
Yet there is little reason to deny
consciousness to animals, preverbal infants [see "The
Conscious Infant," Consciousness Redux; Scientific
American Mind, September/October 2013] or patients with severe
aphasia, all of whom are mute.
Studying their feeding and sexual
behaviors for several decades - Darwin was after all a naturalist
with uncanny powers of observation - he concluded that there was no
absolute threshold between lower and higher animals, including
humans, that assigned higher mental powers to one but not to the
Their constitutive proteins, genes, synapses, cells and neuronal circuits are as sophisticated, variegated and specialized as anything seen in the human brain. It is difficult to find anything exceptional about the human brain. Even its size is not so special, because elephants, dolphins and whales have bigger brains.
Only an expert neuroanatomist, armed
with a microscope, can tell a grain-size piece of cortex of a mouse
from that of a monkey or a human. Biologists emphasize this
structural and behavioral continuity by distinguishing between
nonhuman and human animals. We are all nature's children.
A much more reasonable assumption is that until proved otherwise, many, if not all, multicellular organisms experience pain and pleasure and can see and hear the sights and sounds of life.
For brains that are smaller and less complex, the creatures' conscious experience is very likely to be less nuanced, less differentiated and more elemental.
Even a worm has perhaps the vaguest sense of being alive. Of course, each species has its own unique sensorium, matched to its ecological niche. Not every creature has ears to hear and eyes to see.
Yet all are capable of having at least
some subjective feelings.
Everything that is physical also possesses an interior mental aspect. One is objective - accessible to everybody - and the other phenomenal - accessible only to the subject.
That is the sense of the quotation by
British-born Buddhist scholar
Alan Watts with which I began
If the system falls apart, consciousness
ceases to be; it doesn't feel like anything to be a broken system.
And the more complex the system, the larger the repertoire of
conscious states it can experience.
Consider the wetness of water, its ability to maintain contact with surfaces. It is a consequence of intermolecular interactions, notably hydrogen bonding among nearby water molecules.
One or two molecules of H2O are not wet, but put gazillions together at the right temperature and pressure, and wetness emerges. Or see how the laws of heredity emerge from the molecular properties of DNA, RNA and proteins.
By the same process, mind is supposed to
arise out of sufficiently complex brains.
So if there is nothing there in the first place, adding a little bit more won't make something. If a small brain won't be able to feel pain, why should a large brain be able to feel the god-awfulness of a throbbing toothache? Why should adding some neurons give rise to this ineffable feeling?
The phenomenal hails from a kingdom
other than the physical and is subject to different laws. I see no
way for the divide between unconscious and conscious states to be
bridged by bigger brains or more complex neurons.
Charge is not an emergent property of living things, as originally thought when electricity was discovered in the twitching muscles of frogs.
There are no uncharged particles that in the aggregate produce an electrical charge. Elementary particles either have some charge, or they have none. Thus, an electron has one negative charge, a proton has one positive charge and a photon, the carrier of light, has zero charge. As far as chemistry and biology are concerned, charge is an intrinsic property of these particles.
Electrical charge does not emerge from non-charged matter.
It is the same, goes the logic, with
consciousness. Consciousness comes with organized chunks of matter.
It is immanent in the organization of the system. It is a property
of complex entities and cannot be further reduced to the action of
more elementary properties. We have reached the ground floor of
Philosopher John Searle of the University of California, Berkeley, expressed it recently:
Indeed, if consciousness is everywhere, why should it not animate the iPhone, the Internet or the United States of America? Furthermore, panpsychism does not explain why a healthy brain is conscious, whereas the same brain, placed inside a blender and reduced to goo, would not be.
That is, it does not explain how
aggregates combine to produce specific conscious experience.
It postulates that conscious experience is a fundamental aspect of reality and is identical to a particular type of information - integrated information. Consciousness depends on a physical substrate but is not reducible to it.
That is, my experience of seeing an
aquamarine blue is inexorably linked to my brain but is different
from my brain.
To be conscious, then, you need to be a single, integrated entity with a large repertoire of highly differentiated states.
Even if the hard disk on my laptop exceeds in capacity my lifetime memories, none of its information is integrated. The family photos on my Mac are not linked to one another.
The computer does not know that the boy
in those pictures is my son as he matures from a toddler to an
awkward teenager and then a graceful adult. To my computer, all
information is equally meaningless, just a vast, random tapestry of
0s and 1s. Yet I derive meaning from these images because my
memories are heavily cross-linked. And the more interconnected, the
more meaningful they become.
From this calculation, the theory derives a single number, Φ (pronounced "fi") [see "A Theory of Consciousness," Consciousness Redux; Scientific American Mind, July/August 2009].
Measured in bits, Φ denotes the size of the conscious repertoire associated with the network of causally interacting parts being in one particular state.
Think of Φ as the synergy of the system. The more integrated the system is, the more synergy it has and the more conscious it is. If individual brain regions are too isolated from one another or are interconnected at random, Φ will be low. If the organism has many neurons and is richly endowed with synaptic connections, Φ will be high.
Basically, Φ captures the quantity of consciousness. The quality of any one experience - the way in which red feels different from blue and a color is perceived differently from a tone - is conveyed by the informational geometry associated with Φ.
The theory assigns to any one brain state a shape, a crystal, in a fantastically high-dimensional qualia space. This crystal is the system viewed from within. It is the voice in the head, the light inside the skull. It is everything you will ever know of the world. It is your only reality. It is the quiddity of experience.
The dream of the lotus eater, the mindfulness of the meditating monk and the agony of the cancer patient all feel the way they do because of the shape of the distinct crystals in a space of a trillion dimensions - truly a beatific vision.
The water of integrated
information (IIT) is turned into the wine of experience.
The theory has most recently been used
to build a consciousness meter to assess, in a quantitative manner,
the extent to which anesthetized subjects or severely brain-injured
patients, such as Terri Schiavo, who died in Florida in 2005,
are truly not conscious or do have some conscious experiences but
are unable to signal their pain and discomfort to their loved ones
Consciousness Meter," Consciousness Redux; Scientific
American Mind, March/April 2013].
That is, every person living in the U.S.
is, self by self, conscious, but there is no superordinate
consciousness of the U.S. population as a whole.
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 1019 transistors, about the number of
synapses in the brains of 10,000 people. Thus, its sheer number of
components exceeds that of any one human brain. Whether or not the
Internet today feels like something to itself is completely
speculative. Still, it is certainly conceivable.
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.