Could you be an unconscious zombie and not even know it?

As humans, we live in a world of feeling, that is our experience of the world always feels like something either good or bad, but does it truly have to be that way and, perhaps more importantly, why is it that way in the first place?  The only way to answer the question is to consider the evolution of consciousness.

In 1996, the philosopher David Chalmers proposed an interesting thought experiment to illuminate the challenge of explaining consciousness, that is the feeling of something happening, in purely physical terms.  He asked us to imagine an organism identical to ourselves, literally our exact twin “molecule for molecule,” except without conscious experience.  You are “gazing out the window, experiencing some nice green sensations from seeing the trees outside, having pleasant taste experiences through munching on a chocolate bar, and feeling a dull aching sensation in [your] right shoulder.”  The unconscious zombie, however, “will be awake, able to report the contents of his internal states, able to focus attention in various places, and so on. It is just that none of this functioning will be accompanied by any real conscious experience. There will be no phenomenal feel. There is nothing it is like to be a zombie.”  From there, he insists that if we can conceive of the existence of such a creature, it is possible one exists and, if one exists, then consciousness cannot be physically explained.  This is another way of restating the classical Descartes mind and body duality.  Bodies exist in the physical world and are governed by physical law.  Minds exist somewhere else and are governed by some other, as of yet, unknown physical laws.  It’s also known as the “hard problem” of consciousness.  That is the belief that we can eventually explain the mechanism behind our senses, how light stimulates the rods and cones in our eyes, the stimulation is translated into nerve activity, and the nerve activity is used to assemble what we see.  We can even explain the workings of our thoughts themselves, but why things feel the way they do or even why they feel like anything at all is beyond our current understanding, if not our understanding entirely.

There are many that disagree with this belief for various reasons.  Some have taken issue with the hypothetical existence of the unconscious zombie in the first place, arguing that a molecule by molecule copy of a person would carry consciousness with it.  We might not understand consciousness, but we have no reason to assume that it’s completely separable from our physical bodies.   Keith Frankish, a philosopher with the University of Sheffield and Crete explained it this way to Aeon magazine:  If we were to reimagine the thought experiment with a television set, are we to believe that all of the electronic processes could occur exactly as they were in the original copy, but no picture would appear?  Regarding the brain, he noted, “I think if you really could understand everything the brain is doing – its 80 billion neurons, interconnected in goodness knows how many billions of ways, supporting an unimaginably wide range of sensitivities and reactions, including sensitivities to its own activity … If you could really imagine that in detail, then you wouldn’t feel that something was left out.”  Others take issue with the concept of what we can conceive at a given point of time.  Perhaps our ability to conceive of an unconscious zombie is simply wrong in the first place.  The physicist Sean Carroll provided a comparison to our early understanding of mathematics.  “If you went back 10,000 years and explained to someone what a prime number is, and asked: ‘Is it conceivable to you that there’s a largest prime number?’ Well, they might say ‘yes’; as far as they can conceive, there could be a largest prime number. And then you can explain to them, no, there’s a very simple mathematical proof that there can’t be a largest prime number. And they go: ‘Oh, I was wrong – it’s not conceivable.’”

We can also question whether or not the thought experiment is verifiable when we have no means to look into another’s brain or test that they are conscious.  The famous (or infamous, if you prefer) Turing Test comes closest, but here we are relying on the responses of another, vetting them and comparing them to our own to determine if the being we are conversing with is intelligent.  The opacity of other minds prevents us from ever knowing for sure.  I cannot say for certain that even my own wife is conscious; I can only assume she is because of how we interact.  If an unconscious zombie had all of the capabilities of consciousness except without consciousness, would they not be able to fake a Turing Test and if they could do that, why would we conclude they weren’t conscious in the first place when we could never know for sure?  Likewise, Mr. Chalmers makes an implicit assumption that consciousness doesn’t do anything meaningful, that we can think and act the way we do without it.  As Sean Carroll put it, “The zombie concept is only coherent if you think that none of our conscious experiences have any influence whatsoever on our behavior.”  Needless to say, some philosophers disagree.  Philp Goff, author of Galileo’s Error, argues that there’s “no contradiction in the idea that something with the same physical nature could lack an inner subjective life,” concluding “there is no inconsistency or incoherence in the idea of a zombie.”  Mr. Goff clarified his position on Twitter, making a comparison to a computer’s hardware and software.  “The same software can be run on different hardware, it obviously doesn’t follow that the hardware doesn’t do anything … Likewise, the thesis that human behavioural functions could be realised in non-conscious zombie stuff doesn’t entail that human consciousness doesn’t do anything.”  This is a challenging position to take for two reasons.  First, it’s essentially a circular argument.  In order to behave the way we do, the zombie would have to recreate the effect of consciousness, at least in parts, without having access to the whole.  Second, the statement itself lacks any context without clearly stating what consciousness does in the first place.  If we have no workable definition of the impact of consciousness, how can we say with any clarity that human behavioral functions can persist without it?

Unfortunately, philosophers and scientists alike have been confused about this topic as long as it has been a topic, perhaps starting with Descartes’ famous “I think therefore I am.”  Mr. Frankish believes consciousness is a fiction, something “written by our brains in order to help us track the impact that the world makes on us.”  Mr. Goff asserts that everything is conscious to some degree, avoiding the issue by using a meaningless definition for a condition we all experience.  The concept is known as panpsychism, leading some to proclaim that everything from insects to inanimate objects have some form of consciousness.  Mr Goff and his colleague defined it for the Stanford Encyclopedia of Philosophy, “mentality is fundamental and ubiquitous in the natural world.”  This belief appears to be increasing in popularity, but it’s difficult to say why.  If everything is conscious, nothing is conscious, and consciousness doesn’t do anything.  In contrast, Mr. Carroll believes consciousness is real within its sphere of influence, “exactly the same way as fluids and chairs and universities and legal codes are real – in the sense that they play an essential role in a successful description of a certain part of the natural world, within a certain domain of applicability.”  In my opinion, this gets closer to the truth, but all of these arguments are missing the most fundamental of all points:  No conscious zombies evolved in the real world.  As interesting and provocative as the thought experiment is, evolution did not produce an unconscious zombie.  It produced a conscious human being, and no account of consciousness can be complete without understanding how it evolved in the first place.  Putting this another way, focusing the conversation and analysis on how humans exist in their modern form and comparing our state of being to a computer, neglects the over 500 million years of the evolution of the nervous system that preceded our arrival on this earth.  The most basic principle of evolution, that is the idea that complex phenomena evolve only gradually, in small, incremental steps, suggests that consciousness could not have sprung into existence with modern humans.  Instead, it must have arisen from what came before, either in stages, or by taking advantage of disparate parts that already existed in the animal kingdom.  Looking exclusively at the end product, gives us the impression that the product was designed like a computer when it wasn’t.  It is the product of all that came before, and consciousness must have come with it, been built from what already existed.

Sadly, there has been very little research conducted on the evolutionary origins of consciousness, though our understanding of the evolution of brains and nervous systems has continually improved since Mr. Chalmer’s 1996 book.  This is true even as it is obvious to anyone who closely observes the world around them in any detail that aspects of consciousness are shared with mammals and other intelligent organisms.  “Is my dog conscious? Absolutely,” asks William Seager, a philosopher at the University of Toronto. “What about my parakeet? I think so. A rat? Probably. What about a snake, or a spider? Spiders act – they seem to want things. They form plans, they hunt, they seem to like to eat things, and they avoid situations that are dangerous. Are they conscious?”  These are valid questions, and point to an evolutionary continuum.  To be clear, panpsychism sees consciousness as some type of continuum, but fails to address where and how it arose. Quoting again from the Stanford Encyclopedia, “For its proponents panpsychism offers an attractive middle way between physicalism on the one hand and dualism on the other. The worry with dualism—the view that mind and matter are fundamentally different kinds of thing—is that it leaves us with a radically disunified picture of nature, and the deep difficulty of understanding how mind and brain interact. And whilst physicalism offers a simple and unified vision of the world, this is arguably at the cost of being unable to give a satisfactory account of the emergence of human and animal consciousness.”  This is not a meaningful or truly verifiable statement in my opinion.  Thus, my proposition that consciousness exists on a continuum should not be taken to mean that all of the creatures mentioned by Mr. Seager are conscious; in my opinion, spiders and snakes are following an instinctual program the same as a computer.  There is no choice in their behavior, and choice is where evolutionary pressures converged to produce the beginning of consciousness.

Evolution is nature’s problem solver.  The problem facing organisms with increasingly complex brains and resulting behavior can be stated quite simply:  How does an organism that can do more than one thing in response to a single stimulus decide what action to take?  Note how this question differentiates higher animals from lower.  The spider only does one thing in response to a stimulus, however complicated that thing may be as spinning a web, for example, is not a simple task.  The dog or even the octopus, however, makes choices based on the totality of the environment confronting it.  The totality of the environment includes the organism’s internal mental state and the outside world.  Consciousness is the fusion of those two opposites, a coherent whole forged out of both internal and external stimulus.  Evolution being a gradual process, the emergence of consciousness had to take advantage of existing response systems.  Almost all organisms respond to pain and physical threats, for example.  In insects, these responses are automatic and occur without conscious interference, but in higher animals these responses are enhanced and layered on top of the external stimulus.  Essentially a mechanism to “tag” it as good, bad, or indifferent, must’ve been adopted from earlier, more direct and primitive responses that overrode all other motor functions.  Consciousness combines these tags, which I would claim are qualia, into a coherent picture of the environment and the organism’s feelings about the environment, allowing it to act in a manner that includes the fullness of its experience.  It might be possible to design a system that behaves the same way, but it is difficult to see how such a system could evolve given the reliance on more primitive stimulus and behavior.  Evolution could not create a new fight or flight response from whole cloth, but it could take that response and adapt it into something else.  In my opinion this something else is consciousness.  For that to be true, however, consciousness would need to impart an evolutionary advantage over the hypothetical zombie organism approach.  Putting this another way, an organism that has this fusion of the inside and outside world would need to benefit from it, both for consciousness to be passed down through the generations and for it to grow increasingly complex.  What advantage might there be?

This question is more difficult to answer given that we will not find any evidence of prior mental states in the fossil record, but perhaps it could be rephrased somewhat, namely what are the disadvantages of not having this fusion?  Meaning, if there were two equivalent animals millions of years ago, one that made decisions based on a coherent view of the world and one that relied on completely disparate systems without the fusion mechanism of consciousness, which would make better decisions?  Phrased this way it seems reasonable that the creature fully embedded in the present with access to the fullness of the experience, and where this fullness was felt viscerally, would have an advantage.  A creature that only had access to stimulus piecemeal would lack a full picture.  Each subsystem, pain, fight or flight, food, etc. would present its own discrete output, making it challenging to see how an organism could prioritize them coherently.  In order to function, each subsystem would need to be weighted individually and then finely tuned by experience and evolution to be effective.  If one were to shift in intensity without the others, it could dominate and limit an organism’s behavioral flexibility.  The coherent picture, however, does not suffer from this flaw.  The disparate systems feed into a continuous whole, separating the input from the output, enabling the organism to act on the most pressing stimulus.  The organism could then continue to evolve both the subsystems and the coherent view, offering them the flexibility of temporarily suppressing a subsystem rather than fundamentally altering it.  The contents of consciousness are also more easily adjusted based on the organism’s experience.  The initial fear response could prove incorrect, a false alarm.   Consciousness, by including memory as part of the experience, enables the organism to adapt during its own lifespan.  Consider a domestic dog:  Our coonhound goes crazy for food like most canines, but when under duress the food response can be suppressed, for example during a thunderstorm.  She is aware of the presence of food, but the totality of her experience causes her not to eat.  Further, she responds differently depending on the intensity of the storm.  Distant thunder gives her pause, but ultimately she will eat.  Thunder shaking the house stops her normal instinct entirely.  It is hard to see how this flexibility could evolve without consciousness, or how if something has this flexibility we would not call it conscious.  How would my dog delegate between these options without having them all present, and real in her canine brain?

Whether I am right or wrong, it seems that this hypothesis has the benefit of being testable.  Thought experiments can be thought provoking, but real science requires real evidence from the real world.  Given that one of the chief aspects of consciousness is its coherence and sense of completeness, meaning the blind man experiences the whole world as their senses are capable of producing rather than a a literal hole where visual input should be like a computer without a screen, and the madman doesn’t not know they are mad, it seems reasonable to start there.  Can we design an experiment that decoheres consciousness in a rat for example?  If so, what are the results?  How does an organism behave without this all encompassing experience?  Is it better or worse off?  We will not know until we try, and we are not likely to try unless we begin to understand consciousness as a product of evolution the same as any other animal behavior or physical trait.