Thursday, March 31, 2011

The "hard" problem of consciousness is pretty mushy

The hard problem of consciousness is silly. Here it is, as summed up here:

The problem is how an entity which is apparently immaterial like the human consciousness – it exists, but you can’t locate it, much less measure it – can have arisen from something purely physical, like the arrangement of cells that make up the human body.

You can say the same for abstract concepts like efficiency, health, power, racism, immensity, height, etc. Can you physically locate efficiency? If not, does that mean that efficiency has a soul, or that it's some overly complicated conundrum? Not really.

And yes, you can measure consciousness. Energy is a great analogy for consciousness, because it's not a physical substance in itself; rather, it's a measurement of the ability of physical objects to perform work. You can't feel, taste, touch, hear, or smell energy, but you can know that it exists, because it, by definition, is nothing more complicated than a capacity. Consciousness is just a measurement of the work done by neurons -- a process; in other words, even if it is not the sum of the neurons themselves, it can be demonstrated to be a property or by-product of the neurons for the same reasons that a tornado or river (or their energy content) can be demonstrated to be properties of physical matter, but are not themselves limited by it.

Just because a process is not limited to an unchanging set of physical matter doesn't mean that it requires magic in order to be explained, or that it is somehow beautifully complex; conceding that this is true for just about any abstraction, process, or measurement while simultaneously allowing consciousness to be an exception is preferential thinking at its worst.

The crux of the article, though, has to do with why people mistakenly believe that they have a soul, which is fine, but the issue is made out to be needlessly complicated:

No one has produced any plausible explanation of how the experience of the redness of red could arise from the actions of the brain. It appears fruitless to approach this problem head-on.

I can't make sense of this at all. Anything that confers an evolutionary advantage, no matter how intuitively incomprehensible it may be to us, will be selected for, because the universe will use any impetus or motivator that it can to keep life going. Analogously, the two options with which we're currently presented as explanations for the universe's existence -- that there was a point in time before which no causes existed, and that causality is infinite -- make no sense to humans intuitively, but that doesn't imply that there absolutely must be a third option.

Your brain's inability to imagine things which it did not evolve to imagine does not in any way demonstrate that those things are not business as usual for reality.

As for the subjective feeling of "being" a soul, or an ego that "pilots" a body, I fail to find this phenomenon any more exceptional than any other evolutionary motivator, including non-sensitive reflexes, or even genetic instructions to consume chemicals. When you say things like, "It's truly a marvel how the brain has devised a mechanism for encouraging the reproductive success of organisms by way of thoughts, feelings, awe, wonder, and a sense of beauty," it just sounds like, "I'm in awe of the fact that living things have the capacity to be in awe," or even, "It's amazing how living things are controlled by genetic instructions for no reason whatsoever" to me.

For future reference, here are some immaterial entities which probably exist, but which also probably do not have souls:

Love
Shyness
Hunger
Bravery
Adolescence
Adultery
Success
Enlightenment
Disgust
Exercise

You know what? This list could contain thousands of items, so I'll stop here. Consciousness is not special.

Update: Maybe the following idea will be of help to those who think that consciousness is special simply because it is slightly more complex than its surroundings:

Consciousness, like rivers or exercise, doesn't merely "exist" -- it happens. Think of anything that happens, and you'll soon realize just how unspecial consciousness really is. Can you quantify a baseball game? Can you hold it in your hands? Can you pinpoint exactly where the game is and label it as a material object? No, but baseball games happen, which is something else that the universe allows for. Consciousness happens; our brains are the stadiums.

8 comments:

  1. I don't understand what makes brains so special. The consensus seems to be that sentience can emerge from deterministic processes. Another, seemingly contradictory, consensus is that only organisms with central nervous systems are sentient. What's so magical about the central nervous system? I can appreciate that, for instance, our brains alone are vastly more complex than a clam. I suppose the singling out of vertebrates is just a simplification along these lines, although I've seen people violently assert it as a fact a couple of times.

    If sentience can emerge from deterministic processes, what makes my brain different from society, the internet, or the jungle? If it takes a central nervous system, how about two humans? Does there emerge sentience from their combined brains? If it is true that sentience can emerge from all deterministic processes, it's going to be a tough job to eliminate it.

    I also do not see the evolutionary advantage of sentience. Note my consistent use of the word "sentience" rather than "consciousness"; this reflects our lack of free will. If our decisions were determined, what difference would it make to natural selection whether we actually perceived pain as painful?

    I could write a computer program that is artificially motivated to chase something. For instance, I could program a virtual thermostat that is motivated to keep the temperature at a certain level. Now whenever the temperature deviates, does the thermostat feel discomfort with the gap between the desired temperature and the intended temperature (and maybe experience the illusion of deciding to relieve it)? Is this discomfort as real as our own? It has to be if sentience is evolutionarily advantageous.

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  2. "Another, seemingly contradictory, consensus is that only organisms with central nervous systems are sentient. What's so magical about the central nervous system?"

    I guess it's a matter of universal versus instance. Flight, for example, is a trait associated with feathers, but only one instance of flight out of the four (birds, insects, pterosaurs, bats) requires feathers. Each instance of a phenomenon or process might require different means in order to exist as an end, but what physical matter is used is irrelevant to the fact that the process "happens." Anything sentient requires a network of some kind -- neural or otherwise -- so even if a network in question cannot be strictly referred to as a "central nervous system," it's going to be performing the same functions. There's also a limit to how simple a network can be before it can no longer facilitate sentience; a bacterium, for example, simply does not have a high enough number of connections in order to achieve a sense of pain and pleasure, let alone a sense of self.

    I don't know anything about molluscs, though. I just know that the specific type of hardware used is secondary to whether the hardware can host sentience software. Brains and central nervous systems certainly aren't so complex that they require out-of-the-way, non-deterministic explanations, but they are nevertheless valuable.

    "If our decisions were determined, what difference would it make to natural selection whether we actually perceived pain as painful?"

    This depends on the organism; not all organisms are designed as optimum survival or reproduction machines. Something like 99% of all genetic mutations lead to deleterious results in their respective genomes -- so it's entirely believable that an organism lacking one motivator possessed by its ancestors would stumble upon sentience by happenstance, and thus survive anyway. It's not so much that sentience is "more" beneficial than its predecessors as it is that sentience is useful for the purpose of survival, and can be "randomly" acquired through the inefficient trial and error process of evolution. Evolution doesn't care what motivators it uses -- just that they do what's parsimonious, which, in this case, is to live long enough to make a copy.

    Furthermore, advantage is relative. For example, a lion doesn't need to be as strong as a Tyrannosaurus in order to kill gazelles. This doesn't mean that Tyrannosauruses are "better" at surviving than lions -- just that lions are good enough.

    It's hard to tell whether the pre-sentient proto-worms which existed prior to the Cambrian explosion needed another motivator to reproduce. The crucial point here, though, is that sentience didn't detract from their ability to do so. "Junk" DNA might exist, and we do still have our appendices, indicating that, as long as a trait doesn't get in the way -- even if it isn't beneficial -- it will be selected for anyway. In this sense, evolution is not a competent selector with advantages in mind, but rather a purely parsimonious phenomenon that "blindly" stumbles upon advantages as it accumulates new traits through mutation and environmental factors.

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  3. Here's how I look at it in line of questioning form:

    1. Is a particular trait physically possible?

    2. If yes, then it may emerge at some point over the course of billions of years, because, in lacking foresight, the process of evolution deals with all genetic mutations, regardless of usefulness. This makes any physically possible mutation something that could manifest at any time during the process.

    3. If a particular trait does emerge in a particular instance, will it cause its host organism to die before reproducing?

    4. If no, then it will be selected for, over and over, until the answer to 3. changes.

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  4. Ah, I was indeed unawares under the impression that a trait would be selected against if it did not make a difference.

    But my point about evolutionary advantage was this: given determinism, how can sentience be a motivator? By sentience, I mean the part of consciousness that is actually subjective. We are or will be able to show pain and other sensations effecting decisions in the brain. Nature can select for or against this, but it cannot select for or against subjective experience of pain as pain.

    Although... the fact that I can think about and speak of this otherwise intangible subjective experience is evidence that it does somehow affect the physical world. Unless the brain "knowingly" generates this subjective experience AND thinks about it, i.e., the experience is not just a side-effect.

    That does actually make sense evolutionarily and philosophically, and draws some boundaries as to what constitutes appropriate hardware.

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  5. "But my point about evolutionary advantage was this: given determinism, how can sentience be a motivator? By sentience, I mean the part of consciousness that is actually subjective."

    I don't view subjective experience as incompatible with determinism, given that every state of work is predetermined by all previous states of work. I'm not sure that I see how sentience cannot have predetermined results, unless you're implying that we have free will or something. But your original statement was:

    "I also do not see the evolutionary advantage of sentience. Note my consistent use of the word 'sentience' rather than 'consciousness'; this reflects our lack of free will."

    So if we don't have free will, what is conflicting with the predetermined results of sentience? When a gazelle experiences intense fear, its reaction is to run, which allows it to survive long enough to reproduce. The results are predictable and based on electrical activity. If this is the case, then sentience "works," which is all that matters.

    You might be thinking of this problem in terms of organisms already having motivation, and then acquiring sentience in order to be "motivated further." This isn't the case; sentience simply does its job.

    If not, feel free to provide a real-world example of what you mean when you say that sentience cannot be an evolutionarily advantageous motivator. Maybe I'm just missing something.

    "We are or will be able to show pain and other sensations effecting decisions in the brain. Nature can select for or against this, but it cannot select for or against subjective experience of pain as pain."

    The most immediate things that natural selection utilizes for its various purposes are genes. Genes are what get "selected," but are nothing more than chemical compounds that dictate whether other chemical compounds get synthesized; what happens in the world at our scale is secondary. It's sort of like how a BIOS needs to be able to allow a system to interact with inputs and outputs, but is unconcerned with which higher-level operating systems get installed on the system.

    I liken sentience to any other higher-level result of genetic expression. Birds' nests might be a good example, actually. In a sense, birds' nests "evolved," as they are the end results of various genetic expressions.

    Evolution will use anything in the environment that it can to motivate living things. When complex problem-solving and tool use evolved, that meant sticks and stones; when sentience evolved, that meant pain and pleasure. Stone tools not only affect decisions in the brain, but were "selected for," just like pain.

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  6. Something else to consider:

    Pain, like any other evolutionary trait, does get selected for and have evolutionary advantages, but natural selection is the process of selection and nothing more. The actual emergence of each genetic trait and its various worldly results is part of the sort-of misnamed "random variation," a separate process.

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  7. My particular use of the word "sentience" might be the problem.

    Consider a human who is in all observable ways identical to you, except that his brain does not generate the subjective experience of pain. When he is pinched, his brain processes the pain and reacts accordingly, but no "soul" ever feels it. When threatened, he will flee or fight as a reaction to the fear, but no "soul" ever feels it.

    In what way are you more likely to successfully reproduce than your "soulless" twin? There must be some way if what I mean by "sentience" is a motivator.

    (The notion of a "soul" is probably false, but I can distinguish between pain as processed by the brain and the actual experience felt by "me".)

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  8. "In what way are you more likely to successfully reproduce than your 'soulless' twin? There must be some way if what I mean by "sentience" is a motivator."

    I don't know, but I also don't know if it matters. Life seemed perfectly capable of being motivated for the first 3 billion years without sentience, but, incidentally, sentience also does the job. The prospect of sentience being no more effective than any other motivator doesn't change its status as motivator.

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