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Author Topic: What is life and where did it come from?  (Read 21380 times)

Offline alancalverd

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Re: What is life and where did it come from?
« Reply #50 on: 21/10/2014 08:51:40 »
I have dormant trees in my garden right now. They are alive, but not growing or doing anything to actively modify their environment or defend themselves (e.g. producing and exuding weedkillers or insecticides). Are they asleep?
 

Offline chiralSPO

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Re: What is life and where did it come from?
« Reply #51 on: 21/10/2014 16:34:39 »
my laptop computer sleeps almost every night  ;)
 

Offline flr

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Re: What is life and where did it come from?
« Reply #52 on: 23/10/2014 22:25:59 »
Are other animals conscious? If so, which? How can we tell? ... How do I know you are conscious--do I take you at your word?

 Related to above questions, perhaps one may find interesting the conference posted on-line at the web-address: http://fcmconference.org/
 See also their 'Declaration': http://fcmconference.org/img/CambridgeDeclarationOnConsciousness.pdf

 

Offline dlorde

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Re: What is life and where did it come from?
« Reply #53 on: 23/10/2014 23:40:25 »
I think an important piece of this debate that has only tangentially been brought up, is which beings have consciousness and which do not?

Are only humans conscious? If so, at what point did the first human have its first conscious thought? Are humans conscious from conception on, or does it "turn on"? Can it turn off?

Are other animals conscious? If so, which? How can we tell? Perhaps plants are conscious... perhaps computers are conscious, we just can't know the answer to any of these questions if consciousness is only self detecting. How do I know you are conscious--do I take you at your word?
An unambiguous definition of consciousness is elusive, but if you take the ability to report awareness of some event as an indicator of human consciousness, you can examine the activity of the brain to see if there is some characteristic neural signature that correlates with this indicator.

Stanislaus Deheane (author of 'Consciousness and the Brain') has done extensive studies on subjects who were given various stimuli at increasing intensities, or masked in various ways, so that there came a threshold point at which they reported being aware of the stimulus. Comparing the brain activity signatures in response to the stimulus, he found that stimuli below conscious awareness would produce limited activity in localised areas of the brain. However, when the stimuli crossed the threshold of awareness, that localised activity developed into a characteristic wave of activation that swept across the brain activating many different areas and 'reverberating' for some time before dying away.

Subsequently, this characteristic activity signal has been used to identify levels of consciousness in patients in a persistent vegetative state - i.e. to distinguish between 'locked-in' syndrome and coma, with great success, even identifying patients that could be stimulated into conscious wakefulness.

Tests on animals have shown that in mammals trained to report awareness, when tested (including macaque monkeys and mice) show similar responses and a similar wide area activation pattern when stimuli reach a certain threshold, suggesting something similar to consciousness. Babies of two months old (I don't know if they've tested earlier ages) show the same wide activation in response to spoken language, and the language areas are involved; interestingly, the response is large, but very much slower than in adults, due to the lack of myelination of the neurons at that age - they effectively think in slow motion.

Plants don't have an integrated information processing system like the central nervous system, so there's no way they can be conscious in the sense that animals are conscious. But it would be interesting to see whether other animals, particularly non-mammals, that show some behavioural characteristics associated with consciousness (e.g. octopuses and some birds) show similar patterns of neural activity when actively responding to stimuli.
 

Offline chiralSPO

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Re: What is life and where did it come from?
« Reply #54 on: 24/10/2014 00:48:22 »
Oooh, something measurable, I like it!

I would bet on octopuses as a likely candidate for having consciousness of some sort, given their obvious intelligence and apparent personality. I'm not sure how similar we could expect it to be to ours though, especially given the autonomy their arms have...

I think I most like the idea of consciousness as an emergent property of our complex neural systems, but as far as I know there is only speculation on what the requirements are to support this emergence. It would be interesting to be able to test and measure several animals for signs of similarity to our consciousness.
 

Offline dlorde

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Re: What is life and where did it come from?
« Reply #55 on: 24/10/2014 14:48:59 »
I would bet on octopuses as a likely candidate for having consciousness of some sort, given their obvious intelligence and apparent personality. I'm not sure how similar we could expect it to be to ours though, especially given the autonomy their arms have...
It's a tricky question - we only have our own consciousness as a baseline; how different from ours must complex behaviours be before we don't recognise or acknowledge them as conscious? If we could establish octopus consciousness, it would necessarily be recognisably similar to ours, but could we ever know how similar?  Their nervous systems are so different - multiple ganglia rather than a single central processor, that our neural activity measures might not be applicable (though I'd bet on some common features).

If we do establish they have similarities of consciousness, it would surely say something profound about consciousness in general, as - being molluscs - they would have evolved it quite independently; which would suggest strongly convergent evolution of intelligence & consciousness even in alien environments and body configurations.
 

Offline yor_on

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Re: What is life and where did it come from?
« Reply #56 on: 24/10/2014 20:37:38 »
I don't know, but I expect at least animals, as dogs, horses, cats etc to be conscious. Although to go from that to define them as intelligent is trickier, but so it is with defining a IQ for a human. If you want, animals have souls :)
=

eh, probably should have made that 'self conscious', knowing that they 'exist'. To go from that to a 'mirror test' in where you expect some animal to recognize itself is more of using 'intelligence' to me. But they have feelings, just as us, and they will feel pain.
« Last Edit: 24/10/2014 20:40:42 by yor_on »
 

Offline flr

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Re: What is life and where did it come from?
« Reply #57 on: 24/10/2014 20:55:58 »
... If you want, animals have souls :)

And what is a soul?  :)

 

Offline yor_on

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Re: What is life and where did it come from?
« Reply #58 on: 24/10/2014 21:01:08 »
heh :)

That was for those wanting it flr. I don't know what a soul is, but it seems to be important for a lot of people. Maybe it's what the Egyptians called 'kaa'? (if that now is the correct spelling of it?)
 

Offline Ethos_

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Re: What is life and where did it come from?
« Reply #59 on: 24/10/2014 22:51:11 »


And what is a soul?  :)
Webster's....soul: "an entity without material reality, regarded as the spiritual part of a person."

That is, of course, if one believes in the after life?
 

Offline alancalverd

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Re: What is life and where did it come from?
« Reply #60 on: 25/10/2014 00:14:30 »

Stanislaus Deheane (author of 'Consciousness and the Brain') has done extensive studies on subjects who were given various stimuli at increasing intensities, or masked in various ways, so that there came a threshold point at which they reported being aware of the stimulus. Comparing the brain activity signatures in response to the stimulus, he found that stimuli below conscious awareness would produce limited activity in localised areas of the brain. However, when the stimuli crossed the threshold of awareness, that localised activity developed into a characteristic wave of activation that swept across the brain activating many different areas and 'reverberating' for some time before dying away.


At last, something measurable, definable, and probably useful! It illuminates the distinction between an autonomic and a conscious response in a powerfully mechanistic way.

My surmise is that the subconscious (autonomic) response is the hardwired firmware that keeps the body alive, and the conscious response derives from learning, i.e. forming soft associations between stimuli and responses. This also bears on intelligence, which to my mind is "the ability to surprise an observer" and comes from making associations which are not clearly directly relevant to the stimulus. 

Consider an oldfashioned "IQ" test involving a set of line drawings. The autonomic response is to fixate on a bunch of black lines on a white paper - a baby will do that. The soft association is to name the shapes, "triangle, circle, boat, fish...." and the intelligence test is to spot the connection between what they represent, and to identify the odd one out or predict the next in the series, i.e. to abstract a common property. This explains some of the objections to conventional intelligence tests (if you've never seen a boat or a fish, or they aren't represented that way in your culture, you can't make the unlearned connection because the learned bit is missing).

Many thanks, dlorde, for a powerful insight.

As for dogs and octopi, yes, they can recognise symbols (principally gestures and sounds, in the case of dogs, and defnitely geometric shapes in octopi) and they can "surprise the observer" by responding nonreflexively. Simple case: I whistle for my dog to come to me. If she is dozing or just randomly sniffing her environment, the learned response is fairly instantaneous, but if she is chasing a rabbit or eating, she makes a conscious decision to finish the job and then come to me.  The element of "surprise" is that I don't always know where she is or what she is doing when I whistle, so she is making a decision based on stuff that she knows and I don't. 
 

Offline dlorde

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Re: What is life and where did it come from?
« Reply #61 on: 25/10/2014 11:25:19 »
Consider an oldfashioned "IQ" test involving a set of line drawings. The autonomic response is to fixate on a bunch of black lines on a white paper - a baby will do that. The soft association is to name the shapes, "triangle, circle, boat, fish...." and the intelligence test is to spot the connection between what they represent, and to identify the odd one out or predict the next in the series, i.e. to abstract a common property. This explains some of the objections to conventional intelligence tests (if you've never seen a boat or a fish, or they aren't represented that way in your culture, you can't make the unlearned connection because the learned bit is missing).
Yes; although it seems to me that in IQ tests (and in general) consciously aware thinking (System 2) is concerned mainly with controlling the focus of attention and marshalling the resources of the powerful parallel processing of the subconscious (System 1) thinking - a bit like a teacher coordinating with a class of smart students, using the suggestions they shout out to solve a problem, using the whiteboard as working memory. The teacher keeps the long term goal in mind, getting the students to solve the problem by continually bouncing their suggestions back to them with new questions. The teacher does none of the low-level problem solving; even when choosing between suggestions to focus on, he'll bounce the decision back to the class - 'what looks like the most likely option?'.

This, to me, feels like a better fit with the short evolutionary history of high-level conscious activity. There hasn't been time to evolve much more than a coordinator (System 2) with a scratch-pad, to harness the one-shot abilities of System 1 thinking into chains of coherent, goal-oriented thought.
« Last Edit: 25/10/2014 11:27:57 by dlorde »
 

Offline flr

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Re: What is life and where did it come from?
« Reply #62 on: 29/10/2014 01:27:34 »

Stanislaus Deheane (author of 'Consciousness and the Brain') has done extensive studies on subjects who were given various stimuli at increasing intensities, or masked in various ways, so that there came a threshold point at which they reported being aware of the stimulus. Comparing the brain activity signatures in response to the stimulus, he found that stimuli below conscious awareness would produce limited activity in localised areas of the brain. However, when the stimuli crossed the threshold of awareness, that localised activity developed into a characteristic wave of activation that swept across the brain activating many different areas and 'reverberating' for some time before dying away.


At last, something measurable, definable, and probably useful! It illuminates the distinction between an autonomic and a conscious response in a powerfully mechanistic way.


Actually it does not say anything about the most important aspect of consciousness: the 1st person subjective experience.
Why should a certain neuronal pathway (no matter how complicated and geometrical complex is) generate subjective experience for that particular individual?

For example, let's assume you have a very powerful experimental technique (NMR or whatever) which can tell exactly what happens in my brain when I eat (say) chocolate. In other words you can determine the neurons excitation pathway that is correlated with what I perceive as 'sweet'.  Well, in such a case you only got a 3rd person view of some neuronal pathway and not the 1st person feel of sweetness. What you will be missing will be the most essential aspect: how is it to feel sweet for me .

We became conscious when neurons are firing a more complex pattern and based on that there are objective criteria to asses if a person is aware based on the brain activity.
But why those neurons and more complex neuronal pathway generate a conscious feel and why "it seems" specifically directed for me only that it generate a sense of self for me only?
How a sense of "self" (and awareness) is generated from something insentient such as neurons and neuronal pathways (and electric circuits)?

 

Offline dlorde

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Re: What is life and where did it come from?
« Reply #63 on: 29/10/2014 11:23:57 »
... Why should a certain neuronal pathway (no matter how complicated and geometrical complex is) generate subjective experience for that particular individual?
I suspect that the answer is likely to be because that neural pathway contributes to (is part of) your awareness, and that's how it feels when that pathway is active. Not very satisfying or explanatory, I know, but sometimes things just are what they are.

Quote
Well, in such a case you only got a 3rd person view of some neuronal pathway and not the 1st person feel of sweetness. What you will be missing will be the most essential aspect: how is it to feel sweet for me .
That's rather obvious - your brain is genetically and developmentally unique, and tailored by your unique lifetime experiences; only you can know how things feel for you because only you feel them, and in a way unique to you. Others can only map your symbolic interpretation onto their own experience.

Quote
But why those neurons and more complex neuronal pathway generate a conscious feel and why "it seems" specifically directed for me only that it generate a sense of self for me only?
Those neurons generate a conscious feel because for humans as a whole that's what turned out to give us a better chance of successfully reproducing (presumably for social reasons). IOW, the 'why' is evolution. I don't understand what you're asking in the second half of that sentence - why should your brain generate a sense of self for only you? who else could it generate a sense of self for, and why would it generate a sense of self for anyone else? Sense of self is intimately connected with your individual physical sensorium - your sensory perspective (seeing, touching, hearing, location, etc.); a sense of ownership (your body & mind belong to you); a sense of agency (that you control your body's actions); internal feelings (you can sense your body regardless of the external environment). These are all specific to you and they don't just exist by default, they are explicitly constructed as part of generating your sense of self.

Damage to the areas that generate these sensations or integrate them into the self that is 'you', can result in weird problems like Cotard's Syndrome (thinking you're dead), Alien Hand Syndrome (thinking your hand - or other body part - doesn't belong to you, or is being operated by someone else), or various forms of dissociation, where you lose your sense of location, or identity, or your sense of self expands to encompass everything around you (trippy!).
 
Quote
How a sense of "self" (and awareness) is generated from something insentient such as neurons and neuronal pathways (and electric circuits)?
For reasonably current details of what we know about the generation and construction of self, I recommend Antonio Damasio's "Self Comes To Mind". As to how neurons firing together make feelings and sensations - as I said above, the mental you is the firings of those neurons, and I don't anticipate a better answer than that's how it is to be an active bunch of neurons connected up in that particular way. We can explain specific aspects of perception and experience in terms of information processing, but only personal experience can tell you what it's like to be the information processor involved.
 

Offline flr

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Re: What is life and where did it come from?
« Reply #64 on: 30/10/2014 16:34:40 »
As to how neurons firing together make feelings and sensations - as I said above, the mental you is the firings of those neurons, and I don't anticipate a better answer than that's how it is to be an active bunch of neurons connected up in that particular way.

 That reflects the view of identity theory that mental states = neuronal states. In short, that just like lightening = electric discharge (or sound = pressure waves through fluids) , the identity theories state that mental states = neuronal states and nothing else.

 However, for A=B , A and B must have the same properties, if B has a property that A does not posses then the equality is not true.
 Then some objections to identity theory could be formulated as follows:
 i) a) neuronal states are physical states and there is an ontologic reality of them.
    b) there appears be no ontological reality of mental states. For example the 'redness' of the 'red' is how my mind map the red for me. Red exists as ontologic entity but not 'redness'. 'Redness' appears to me as something 'virtual' in my mind only, but the neuronal state that generate 'redness' is real thing.
 ii) a) neuronal states can be viewed by everyone. they can be objectively measurable.
    b) mental states are strictly private to the subject; i.e. only I know what is in front of me now, not you.
 iii) b) mental states have 'about-ness' or intentionality. For example I love my wife. The subject of my mental state 'love' is a person.
     a) neuronal states have no intentionality whatsoever; how could possible a flux of ions/e- care abut my wife?
 iv) b) Based on mental states that follows the rationale: "If A=B is true and B=C is true then always A=C is true" one can understand it as a valid judgment or a truth.
      a) But if you follow with that super-NMR-aparatus all corresponding neuronal states needed to judge the above statement , where in those neuronal states (which again, are no more that ions/e- flux) is the value of truth?

===================

There may be a principal problem with the token identity theory:
 Let's assume that in a billions years from now a super-advanced tech/civ. can duplicate exactly the brain of AAA, into a new copy BBB. I would expect that BBB has its own private mind as it is a brain separated from AAA. But the neuronal states on BBB which are identical to those in AAA brain (they are exact copies) do not generate mental states in AAA but instead in BBB. That would negate the token identity theory.

==============

  It appears to me that mental states are caused by neuronal states but not identical to them. That means: there is still a missing piece needed to explain how mental arises from physical states.
 

Offline flr

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Offline PmbPhy

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Re: What is life and where did it come from?
« Reply #66 on: 02/11/2014 21:22:32 »
Has anyone ever read Schrodinger's book What is Life? It's online and can be downloaded at http://bookzz.org/book/651226/daa6c9
 

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Re: What is life and where did it come from?
« Reply #66 on: 02/11/2014 21:22:32 »

 

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