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What is the purpose of sentience?

  1. Nov 25, 2011 #1
    What function does it serve? Assuming that my brain is just a computer run entirely by deterministic and/or probabilistic processes, why does there have to be a "passenger along for the ride"?

    When I talk about sentience, I am referring to your ability to experience experiences. Many would say that it allows us to think or make decisions, but our computers do this just fine and they are not aware of themselves. Isn't the human body and brain just a machine that responds to input that it receives through the senses? Why does there have to be an entity within that experiences this life?
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  3. Nov 26, 2011 #2


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    Last edited: Nov 26, 2011
  4. Nov 26, 2011 #3
    It is hard to know where your hands and feet are unless you are aware of where your hands and feet are.

    Sentience derives from that requirement.
  5. Nov 26, 2011 #4
    Vendicar, couldn't our body do all these things the same way that a computer does them? Computers are not conscious, and are capable of intelligence, and decision making. Why doesn't the brain just run on algorithms such as "BEAR = RUN"?

    Or does a computer just develop sentience once it gets intelligent enough? Or are "senses" required to exist?
  6. Nov 26, 2011 #5


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    I think the question is very hard to answer, because we don't have an operational definition of sentience. Typically, to answer a question in science we have to be able to say if you do the following experiments and get these results, then by the data are consistent with a theory in which X is true. But we don't have experiments that are able to tell us whether a thermostat or a human being is sentient or not.

    One note is that there are many "qualities" which are not either-or. For example, the distinction between liquid and gas. You may encounter regimes where it looks like the distinction is sharp. Yet if you go around the critical point, there will not be a phase boundary. And if you look closely enough, even the phase boundaries are not perfectly sharp in real life, since they require an infinite number of atoms, whereas real liquids only have ~10^23 atoms.
  7. Nov 26, 2011 #6


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    Computers run programs and are limited to the information they are given. Also, you need to back up any extraordinary claims of fact with published mainstream scientific papers that back you up.
  8. Nov 26, 2011 #7
    You're assuming that animals don't have any consciousness. It's probable that animals have different levels of consciousness. Humans probably have the highest level of consciousness on Earth but other animals probably have consciousness appropriate to their lifestyle. I'm convinced that my cat, for example, does not just react to stimuli. She does thing that, to me at least, appear to involve decision making. In the same way that I might want to read a book or watch TV my cat does similar things in terms of her normal day to day routine.
  9. Nov 26, 2011 #8
    Bear = run

    What direction? Into a tree? Into a wall? Into the arms of another waiting bear?

    The signal is bear. The correct response however is dominated by the noise of the environment around you.

    Running away at 180' from the bear is probably the best choice until the bears become smart enough to hunt in packs and smart enough to know your programmed response to turn 180'.

    They you are soon extinct as a species.

    Programmed responses are what machines currently rely upon, and if you notice, you might see that they make pretty poor robots for that reason.
  10. Nov 26, 2011 #9
    "Or are "senses" required to exist?"

    The brain thinks by modeling the world. It does so through modeling the sensory inputs available to it. Without sensory inputs, you can not model the world in that manner and will have difficulty in thinking about the world around you since you will have not adequately experienced it.

    Think about changing the inner tube on a bicycle. Your plan will involve a visual model of how to move the tools, how the tire will look when removed, how the tube needs to be placed, etc.

    It will also involve a sense of where your hands are in space. How they are oriented to hold the tools, what pressure is used to perform the tasks etc.

    You might also model the smell of the new tire, the sound of the spokes, or the sprocket retaining nuts entering a magnetic tray, or your pocket, or the ground.

    You may also model getting oil on your fingers, and then on your shirt, and watch yourself place that shirt into the washing machine, or washing it by hand at a sink.

    All of the planning for changing the tire is sensory modeling. You may throw in a word or two in your own inner dialog to keep track of things. But that too is a model of the sensory input of hearing.

    Without such inputs, Computers will continue to have difficulty interacting in the real world.
  11. Nov 26, 2011 #10
    All higher order animals are both conscious and self aware. That is self evident from their behaviors.

    Dogs and cats suffer from depression, and experience love, joy and loss, bliss, anger, frustration, and all of the other emotions that people have.

    These emotions exist for evolutionary purposes, and are probably heightened in social animals where they are "used" to provide cohesiveness to the group.

    Where people differ from other animals is in the self recognition of those emotions and their subsequent heightening by means of self reinforcement due to that recognition.

    Even crows have been shown to have an advanced sense of self awareness. Like Elephants they even recognize themselves - along with errors in their plumage - in mirrors.
  12. Nov 27, 2011 #11


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    A modern phone could probably make that decision for you very satisfactorily, without the (apparent) need for sentience.

    The OP asks a good question because AFAIK there's no established or even theoretical connection between sentience and computability or efficiency, which is at the heart of the problem.
  13. Nov 27, 2011 #12
    "A modern phone could probably make that decision for you very satisfactorily"

    Why would a modern phone want to?
  14. Nov 27, 2011 #13
    "Purpose" is not appropriate unless you're buying into some superior being who/that rationally established the capability.
    Reference to "function" is much better and you answer your own question in description.
  15. Nov 27, 2011 #14


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    ...kind of missing the point...

    The point was that many kinds of decisions can be made with a very simple processor. The suggestion that animals need to decide to evade a threat does not lead to the need to sentience.
  16. Nov 27, 2011 #15


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    There is some data suggesting that consciousness is a product of epiphenomenalism. In other words consciousness actually plays no part in the decision making process, rather conscious thought lags behind. However there remains an illusion of consciousness being the decision making agent. The data isn't solid yet and it's still largely an unexplored area but it could suggest that consciousness is a by product of intelligent agency rather than the agent itself.
  17. Nov 27, 2011 #16
    We have to be careful when we ask questions about the "purpose of something." "Why" questions are inherently unscientific. I could present an evolutionary argument for how sentience could prove to be advantageous to an organism's survival. The answer to these types of questions can normally be explained using evolution. Sentience served the function of helping your ancestors grow and reproduce more effectively in the environment in which they were in. Our computers do not think and make decisions "just fine." Sentience may very well be a key component of what we call intelligence.
    Last edited: Nov 27, 2011
  18. Nov 27, 2011 #17
    "The point was that many kinds of decisions can be made with a very simple processor." - Dave

    And they are generally made with a very simple processor - the spinal column.

    But you miss the point entirely. Why should a non-sentient organism associate a bear with a complex pattern of response that is tailored to it's environment? And how would such a system evolve without higher level processing.

    Why would a cell phone wish to escape from a bear? How would it evolve such a response without self awareness?

    Is the cell phone going to fear being eaten? How and why? Fear itself is a manifestation of sentience.
  19. Nov 27, 2011 #18


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    Again I think you are missing the point. The argument being presented to you is that an artificial intelligence can be programmed to react to a situation and potentially even be programmed to learn/adapt. It does not need emotion or instinct to make it act, action is simply a part of it's programming. And as objects like computers have no consciousness that we can identify the argument being put to you is suggesting that consciousness (and emotion) are not a necessary partner of intelligence.

    Also please learn to use the quote button. If you want to respond to someone press the quote button on the bottom right of their post.
  20. Nov 27, 2011 #19
    "..consciousness is a by product of intelligent agency rather than the agent itself." - Ryan

    Clearly it is both an observer of decision and a decision maker. I have made a conscious decision to have eggs for dinner. That conscious decision will drive my response. At other times, when I am driving myself through the day, my consciousness monitors my automatic processes and on occasion modifies them for my conscious amusement or to further some plan of action.

    Still the component actions themselves are unconsciously driven.

    Now it could be argued that my decision to have eggs for dinner wasn't so much a conscious decision but just the monitoring of the result of a weighting of various factors by my unconscious. But if that is the argument (and I agree with it), I have to wonder if such a position pushes the definition of consciousness into a position where by definition the supposition that by definition no conscious decision is possible.

    So what do you mean by conscious decision?
  21. Nov 27, 2011 #20


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    If you read the link I provided epiphenomenalism suggests that conscious decisions are an illusion. It is proposed that all decision making is subconscious and the body moves to act on those decisions milliseconds before conscious thought of it occurs. This would suggest that consciousness is sort of like a real time memory rather than the decision making process itself. A good book that explores this is Blindsight by Peter Watts.

    If you are having trouble getting your head around this think of it this way: there is a car with a driver. The driver uses their hands and feet to turn the wheel, press the peddles, change gears etc. What they don't realise is that the car is driving itself and all of the buttons, peddles, wheel etc are actually moving slightly before he touches them. But as he never stops trying to drive the car he never realises.

    Now this isn't fact, there is some suggestive data and the jury is still out.
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