Sentience in fish

Studies of mental functions, behaviors and the nervous system.

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Re: Sentience in fish

#41  Postby Mr.Samsa » Jul 28, 2011 6:37 am

ughaibu wrote:Didn't you define sentience in terms of adaption rather than experience? Anyway, I see your point.


I don't think so - if I did, then that was a mistake. I've been using the definition of sentience as "the ability to experience". I did attempt to use Stenhouse's definition of intelligence as a definition of learning though; i.e. "adaptively variable behavior".
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Re: Sentience in fish

#42  Postby ughaibu » Jul 28, 2011 6:41 am

Okay.
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Re: Sentience in fish

#43  Postby zoon » Jul 28, 2011 10:39 am

Mr.Samsa wrote:Is it possible that you're interpreting "consciousness" as "awareness"?

What distinction would you make between the two? The Oxford dictionary defines “conscious” as, first, “aware of and responding to one’s surroundings”.

Mr.Samsa wrote:
Firstly, I think I might have been unclear when I described the basic behavioral law that controls behavior. This is not a claim or belief of behaviorism, it is a conclusion from behavioral research. That is, Skinner didn't say "All behavior must or should be controlled by basic pain and pleasure principles". Instead, it just turns out that all behaviors that have been studied and understood have all been reducible to things like the matching law, or the contingency discriminability model. Essentially, all behaviors are reduced to choice theories because all behavior is choice behavior; so whenever you choose to do something (e.g. wave your arm around), you necessarily choose to refrain from doing something else. And all the currently available choice theories rely on "pain" and "pleasure" parameters.

A thermostat can be programmed to close a switch in response to a sensed temperature above a certain level (a heating mechanism is then closed and the thermostat cools). It would also be possible to program the thermostat to learn to close the switch, for example, if a light flash was followed on two occasions by a rise in temperature above the set level, the thermostat could be programmed to close the switch after any further light flashes, instead of waiting to sense the temperature going up.

If a thermostat was programmed to learn in that way, then presumably the thermostat, after learning from two or more light flashes followed by a rise in temperature, chooses the behaviour of closing the switch when the light flashes. This would be because the thermostat has pleasure in a cool temperature and pain when the temperature gets too high? Someone who did not know anything about programming or thermostats might reach that conclusion, after observing its behaviour. And that method of predicting the thermostat would actually be correct, it would work – the thermostat acts to reduce temperatures above the set level, or when it’s learnt that the temperature is likely to go above the set level. Pragmatically, the thermostat would be correctly described as reacting to painful or pleasurable stimuli, and as learning.

However, for anyone who did know about thermostats and programming, the available theories would not be limited to reliance on “pain” and “pleasure”. There would be an alternative explanation for the thermostat’s behaviour in terms of electrical circuits and the properties of switches and heating mechanisms.

It seems to me that “pain” and “pleasure” are useful markers for ignorance, when we don’t know the physical mechanism for an animal’s behaviour (the mechanisms in even the simplest creatures like bacteria are fantastically complex and barely beginning to be understood).

When we use “pain” and “pleasure” as explanations, we are using Theory of Mind, which humans use more than other animals. We probably evolved it primarily to predict fellow humans, but it also works for predicting many non-human animals. If I say an animal, or a thermostat, acts in response to pain, then I’m putting myself in the place of the animal, or thermostat, and predicting what I would do. This all goes on unconsciously, I’m not deliberately pretending to be a thermostat, I’m just using my own action circuitry to predict what the thermostat will do, and it works.

In the case of a thermostat, I’m not limited to the Theory of Mind pain-and-pleasure-type explanation, because we know the actual mechanisms of thermostats. But in the case of animals, we don’t yet know the actual mechanisms, so we use the Theory of Mind explanation because it is the next best way of predicting what they will do. The Theory of Mind explanations, in terms of pleasure and pain, are not in fact wrong, they work - predicting a thermostat in terms of pleasure and pain is as correct as predicting it in terms of physical mechanism. (But predictions in terms of pleasure and pain are less detailed, so pleasure and pain type explanations tend to be superseded by mechanistic ones when the mechanisms are understood.)

When we use Theory of Mind to predict an object, we are using our own response mechanisms to predict what the object will do. We have the feeling that the object is conscious or aware (I’m not sure what distinction Mr Samsa is making) because we have activated a shadow response. It may or may not be the case that the object (animal or human or thermostat) actually has consciousness or awareness or sentience, I don’t think it matters.

There’s the separate question of whether an object with sentience should be treated with consideration and kindness. In a globalised world where humans seriously need to cooperate with lots of strangers, it is probably important to have a blanket rule to treat anything like us with compassion, whether or not we understand ourselves in terms of physical mechanisms. How far down the phylogenetic scale this goes, and to what extent it should be regulated by law, looks like a matter of endless debate.
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Re: Sentience in fish

#44  Postby rEvolutionist » Jul 28, 2011 11:41 am

Mr.Samsa wrote:
rEvolutionist wrote:
Mr.Samsa wrote:Out of interest, what kind of arguments do you have in mind for why it might be rational not to eat something with which we shared a common ancestor?


My approach has always been related to cognitive intelligence. Those more able to abstract their surroundings and contemplate them would seem to show a higher level of intelligence (and therefore have more to lose). Even if this was considered to be anthropomorphising, it is still relevant as it is humans who are doing the choosing whether to eat or not. I don't see any advantage in using any other reference system of beliefs/determinants to decide whether I should eat something or not.


You seem to be describing "sapience" here.


Probably. As I said, more "sapient" beings will have greater sense of potential loss, will have a greater understanding of what is happening to their fellow animals that are being killed for consumption. They're more likely to be able hypothesise about the future and potentially suffer more due to that. Would you agree that "suffering" would be greater for more sapient creatures?

There is nothing necessarily wrong with this, but it does fall into the trap Hugh describes above of valuing things which are human-like.


Why is that necessarily a "trap"? :ask:

As I said, I see no reason to attribute more or less importance or significance to this value system over another. And in a way it makes more sense, as it is the most relevant system for us to utilise as humans.

rEvolutionist wrote:
You'd probably be in a better position than me to say whether it's true or not, but I assume that anything that can respond to its environment must have some mechanism for interpreting external signals. Whether these are nerves, or vascular strands or roots etc, seems irrelevant to me.


Ok, I see what you are getting at. Up to this point in my life (although doubts have been forming since debating with you about cognition), I have been of the belief that there is such a thing as higher order processing (or what I call - and have read as - cognition). I.e. bundle a few bazillion synapses together and you wind up with this emergent thingy that no one other than behaviourists can seem to explain. Plants don't have that. Usually I would say that plants react to their environment in a direct chemical/physiological way. Humans et al, obviously do this in both a reflexive sense and a higher order cognitive sense, but in the case of the latter, the chemical/physiological responses are so far removed/abstracted from the stimulus as to be nothing like the same process that goes on in plants. But I need you to answer those behavioural questions I posed, so that I can be sure of what I am agreeing with and what I am arguing about. (oops, i see they are down below. I'll get back to this point).


Indeed, there are higher order cognitive processes and we can be fairly sure that plants don't have these (and as for the cheap shot :lol: , behaviorists have no problem explaining emergent cognitive processes). But of course higher order processes aren't necessary for the experience of pain (or aversive stimulation) since such an experience is fundamental to all living things. The question then simply becomes whether it is reasonable to cause something to suffer just because it has no understanding of astrophysics or algebra?


I'd just reiterate my point from above. Surely greater sapience implies greater ability to suffer, yes?

EDIT: I forgot to mention this, but plants don't just respond in a 'chemical/physiological' way (at least no more than animals). They actively employ methods to avoid pain, even without the painful stimulus present, etc. There is more complex learning and behavior involved in plants, and not just a simple cause-and-effect type response.


I didn't read Trewaras' (sp?) big paper, but read his shorter one in Nature. I can't say I was convinced by anything he said. Perhaps there was something extra in his big paper that wasn't in the shorter one? He didn't seem to give many examples in the shorter one, other than direct physiological reactions to stimulus (like growing towards light, or away from adverse soil conditions).

rEvolutionist wrote:
ughaibu wrote:There's a danger of triviality here as it seems that any behaviour might imply sentience.


This is in a sense my main beef with behaviourism (well, my limited understanding of it so far). It's a self-fulfilling theory. By it's very definition it can't be wrong.


Behaviorism isn't a theory, it's a methodology. It can't be right or wrong in the same way "biology" can't be right or wrong. The only way it can be ignored or rejected is if it can be shown to be useless or unable to predict the subject matter it seeks to explain.


It's tenets could be wrong in the same way that biology's tenets could be wrong. But the underlying tenet of behaviourism - that behavioural organisms seek pleasure and avoid pain, is unchallengeable. There's no scenario that can be presented (well, that I can think of anyway) which couldn't be addressed by this tenet. Someone could naively say that those choosing suicide over life would be seeking pain and avoiding pleasure. But the obvious answer to this is that the person is seeking pleasure by avoiding the pain of life.

I'm not saying anything about the veracity of Behaviourism here. I find it absolutely fascinating. Before I read what you had to say about it, I knew next to nothing about it. In fact, it seems the beautiful simplicity of it is its strongest point (i.e. it can effectively answer all questions about the act of living - at least at a general level).

rEvolutionist wrote:
Mr.Samsa wrote:I don't know if it's absolutely true, it's possible that there are complicating details or even completely new fundamental laws of behavior that need to be considered, but I think that at least for the vast majority of behaviors that we ever talk about, that behavioral law can account for all of them (obviously excluding innate behaviors).


A quick follow up question to this:
Where does this behaviour come from? As I suspect you are going to essentially say 'evolution', I'll go further and ask - What supports or maintains this behaviour in an individual?


It's arguable whether it specifically comes from evolution. The behavioral law could be a natural consequence of having an organism that avoids bad things and approaches good things.


I don't get it? Surely "bad things" would have an evolutionary selection pressure?

rEvolutionist wrote:Essentially, How is this behavioural law translated into action (by what mechanism)?


You mean on a neurological level? Long-term potentiation and in-vitro reinforcement appear to the mechanisms which control classical and operant conditioning.


I guess I'm asking how we scale up from say a tree root, or a simple animal, steering away from a negative stimulus, right up to humans abstracting and hypothesising about the future and behaving based on that seemingly immaterial stimulus.

rEvolutionist wrote:There you go: Where, What, How! You have 2 minutes and no more than 3 paragraphs to describe the history and dynamics of behaviourism! :razz:


How'd I do? :dopey: :lol:


Not good enough. :whistle: I want more info. I still don't fully appreciate what it is Behaviourism does and tells us.

rEvolutionist wrote:
Mr.Samsa wrote:Oh okay.. well the Mazur definition I posted also includes the criterion of experience (as does every other definition of learning I've ever seen). How would you define learning?


I think the use of "experience" is correct. "Experience" to me directly implies consciousness. But Sternhouse's "adaptively variable behaviour" doesn't necessarily imply "experience" to me. Firstly, 'adaptive' could be (to use extremes, to simplify my point) cognitive, or it could be directly physiological (Edit: essentially physical/chemical). That alone removes certainty of conscious experience, in my book.


Is it possible that you're interpreting "consciousness" as "awareness"?


I don't know. To continue my reasoning from above, I guess I think that "suffering" requires more than just simple "experience". It requires a deeper experience that implies some sort of understanding of sorts. i.e. Sapience, as you say above.

rEvolutionist wrote:But further to this, the statement "variable behaviour" potentially breaks down when one considers that behaviourism essentially reduces to the fundamental like/dislike paradigm. There can never be 'variability' under such a unifying paradigm. Every particular action in a particular organism at a particular moment in it's life can only ever be one of either a
'like' or a 'dislike' driven event. i.e. no room for variability. Your thoughts?


Firstly, I think I might have been unclear when I described the basic behavioral law that controls behavior. This is not a claim or belief of behaviorism, it is a conclusion from behavioral research. That is, Skinner didn't say "All behavior must or should be controlled by basic pain and pleasure principles". Instead, it just turns out that all behaviors that have been studied and understood have all been reducible to things like the matching law, or the contingency discriminability model. Essentially, all behaviors are reduced to choice theories because all behavior is choice behavior; so whenever you choose to do something (e.g. wave your arm around), you necessarily choose to refrain from doing something else. And all the currently available choice theories rely on "pain" and "pleasure" parameters.


That's fine, I wasn't implying otherwise. It also doesn't change what I was saying.

Secondly, you're defining "variability" too narrowly. The "variable" in "adaptively variable behavior" simply means that the topography of a behavior can change in response to the same task or challenge. So if we put a rock in a maze, it's unlikely that it will find the cheese at the end. If we put a wind-up car in a maze, it's unlikely it will find the cheese at the end, etc, but if we put a rat in a maze, it will display a number of behaviors (e.g. 'go straight', 'turn left', 'turn right' etc) and this variability in behavior is adaptive (i.e. incorrect responses are extinguished, and correct ones are strengthened).

Yeah, I get what you are saying, but I guess it depends on the ability to separate variable movement out from an invariable "drive". As an example of what I am trying to say, think of a tree growing in part shade under other trees. There is an invariable goal "driving" its growth, and that is the need to get more sunlight on its leaves. But depending on other variables - herbivores, disease, wind, humidity etc. - it might display a different "behaviour" by growing towards a different area of higher light. But I wouldn't say this plant is showing variably adaptive learning. Perhaps this isn't the best analogy, as you might very well say that the plant is displaying this.

Meh, i've agonised over this paragraph for a while now and I just can't nail what I am trying to say. I'll leave it half out there, in case it prompts me at a later point to get to the crux of my problem.

Indeed - they are obviously tested with novel stimuli. The only way for them to solve the tests is for them to understand the abstract concepts behind the sample stimuli - the nature of grammar, or the style of a painter, etc. There have been numerous tests on musical discrimination, I'm not sure if any have compared Beethoven and Mozart, but here's a test of Bach and Stravinsky. They can also judge how 'good' or 'beautiful' a painting is. (And, if you're interested, here's a study on carp distinguishing between blues and classical music).

The grammar study is here, and followed up here Artificial Grammar Learning in Pigeons, and the statistics study: Are birds smarter than mathematicians? Pigeons (Columba livia) perform optimally on a version of the Monty Hall Dilemma.


Bloody pigeons. I'll never look at them the same ever again!
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Re: Sentience in fish

#45  Postby rEvolutionist » Jul 28, 2011 12:08 pm

Interesting post, Zoon. I think this is along the lines of what I was trying to say. Essentially there is a meaningful distinction between a Theory of Mind and a plant root growing away from unfavourable soil conditions. At what point awareness/consciousness or "suffering" kicks in, I'm not sure. But in terms of extremes, it doesn't seem too controversial to maintain that there is a difference. Now I know Samsa wasn't necessarily talking about plants, but more focussed on animals. I still haven't bothered to look up what sort of nervous systems simple animals have, but even if they do, I'm not sure how we distinguish between cells in plant roots and cells in nerves. In fact, I think Samsa asked the same question earlier. So perhaps the plant as a lower extreme for behaviour is valid.
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Re: Sentience in fish

#46  Postby Blip » Jul 28, 2011 3:55 pm

Mr.Samsa wrote:No doubt that both vegetarians and meat-eaters both do this, as well as scientists and practically everybody. But as a counterpoint, ever seen animal rights activists protest against fishing nets because they kill dolphins? This is evidence of the cuteness factor, considering that they don't care about the death of millions upon millions of tuna.


No, I don't think so. Not at all. Firstly, quite a few of those people do care very much about the death of tuna. And you are overlooking the fact that the tuna are at least to be eaten, whereas the wholly-avoidable deaths of the dolphins constitute collateral damage for no purpose whatsoever.

Mr.Samsa wrote:Indeed - they are obviously tested with novel stimuli. The only way for them to solve the tests is for them to understand the abstract concepts behind the sample stimuli - the nature of grammar, or the style of a painter, etc. There have been numerous tests on musical discrimination, I'm not sure if any have compared Beethoven and Mozart, but here's a test of Bach and Stravinsky. They can also judge how 'good' or 'beautiful' a painting is. (And, if you're interested, here's a study on carp distinguishing between blues and classical music).

The grammar study is here, and followed up here Artificial Grammar Learning in Pigeons, and the statistics study: Are birds smarter than mathematicians? Pigeons (Columba livia) perform optimally on a version of the Monty Hall Dilemma.


Fascinating stuff, thank you. I'm predictably perturbed that the birds are kept markedly underweight in order to motivate them to take part, but that's for another discussion. I am not sure that, in the final analysis, these experiments don't simply reveal that pigeons can see and hear while fish can hear, which I knew already.

I'm now wondering if my choice of the word 'sentient' was the best one: I'm used to choosing my words with care, but not in a scientific context. I suppose in the end it's the propensity for suffering that I'm seeking to establish, which takes us into the realms of consciousness, awareness and self-awareness (zoon and rEv speak of this above).

My own research in this area led me long ago to abjure intensively-reared animals (including fish - the sight of salmon trying to escape their captivity in fish farms would distress the hardest of hearts) but my current ethical dilemma is around eating wild fish.

Anyway, it's a fascinating discussion, that notwithstanding.
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Re: Sentience in fish

#47  Postby Blip » Jul 28, 2011 4:32 pm

Forgive the follow-on post but in considering consciousness, awareness and self-awareness, one might look to the example of one's own development, from within the uterus to the present day. I have existed continuously since my conception, but at what point did I become sentient? Conscious? Aware? Self-aware? My own memories commence at about two years old: at that point the last of those then?
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Re: Sentience in fish

#48  Postby cavarka9 » Jul 28, 2011 4:37 pm

hello, sorry for interrupting,is it possible to have a condensed version of where people stand now. Do fish have sentience or not, also we do have pigeons living in our balcony to raise their young-lings, they keep coming into our home, they probably know that we are not threatening.
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Re: Sentience in fish

#49  Postby zoon » Jul 28, 2011 5:24 pm

rEvolutionist wrote:Essentially there is a meaningful distinction between a Theory of Mind and a plant root growing away from unfavourable soil conditions. At what point awareness/consciousness or "suffering" kicks in, I'm not sure. But in terms of extremes, it doesn't seem too controversial to maintain that there is a difference. Now I know Samsa wasn't necessarily talking about plants, but more focussed on animals. I still haven't bothered to look up what sort of nervous systems simple animals have, but even if they do, I'm not sure how we distinguish between cells in plant roots and cells in nerves. In fact, I think Samsa asked the same question earlier. So perhaps the plant as a lower extreme for behaviour is valid.

My rather convoluted view is that where awareness is concerned, the difference between an animal and a plant root is in the way we respond to them, rather than an essential difference between the things themselves. Psychologists and neuroscientists are coming up with a lot of evidence that humans use simulation Theory of Mind, which is an unconscious process for predicting other people, and also for predicting anything that behaves in a vaguely human way, which includes most animals. When I see another person, my brain automatically goes into Theory of Mind mode, so that instead of trying to predict them as if they were machinery, I put myself imaginatively into their place, set up a model of the world as I think they see it, then use my own response mechanisms to predict what they will do. This all happens unconsciously: I don’t think “I’ll imagine what it is like to be that person”, I just see them in terms of beliefs, desires, experiencing pain and so on. This unconscious Theory of Mind process works much better than trying to predict people as machinery, which is why it evolved. The same goes for e.g. looking at a rabbit: predicting it in terms of what it sees or hears, what it wants or is afraid of, works better than trying to predict how its neurons and muscles will react to events. We see people and rabbits as conscious because we predict them using an unconscious mechanism which involves putting ourselves in their place.

Plants generally react too slowly for the Theory of Mind process to be useful in predicting them, so (as I see it) we don’t think of them as conscious. Perhaps a time-lapse film of a plant root probing for nutrients might give the sense of awareness at work?
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Re: Sentience in fish

#50  Postby ughaibu » Jul 28, 2011 5:34 pm

zoon wrote:Perhaps a time-lapse film of a plant root probing for nutrients might give the sense of awareness at work?
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Re: Sentience in fish

#51  Postby rEvolutionist » Jul 29, 2011 12:08 am

Blip wrote:
Mr.Samsa wrote:No doubt that both vegetarians and meat-eaters both do this, as well as scientists and practically everybody. But as a counterpoint, ever seen animal rights activists protest against fishing nets because they kill dolphins? This is evidence of the cuteness factor, considering that they don't care about the death of millions upon millions of tuna.


No, I don't think so. Not at all. Firstly, quite a few of those people do care very much about the death of tuna. And you are overlooking the fact that the tuna are at least to be eaten, whereas the wholly-avoidable deaths of the dolphins constitute collateral damage for no purpose whatsoever.


I still maintain that it is down to "sapience". A dolphin would appear to be more sapient than a Tuna.
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Re: Sentience in fish

#52  Postby rEvolutionist » Jul 29, 2011 12:21 am

zoon wrote:
rEvolutionist wrote:Essentially there is a meaningful distinction between a Theory of Mind and a plant root growing away from unfavourable soil conditions. At what point awareness/consciousness or "suffering" kicks in, I'm not sure. But in terms of extremes, it doesn't seem too controversial to maintain that there is a difference. Now I know Samsa wasn't necessarily talking about plants, but more focussed on animals. I still haven't bothered to look up what sort of nervous systems simple animals have, but even if they do, I'm not sure how we distinguish between cells in plant roots and cells in nerves. In fact, I think Samsa asked the same question earlier. So perhaps the plant as a lower extreme for behaviour is valid.

My rather convoluted view is that where awareness is concerned, the difference between an animal and a plant root is in the way we respond to them, rather than an essential difference between the things themselves. Psychologists and neuroscientists are coming up with a lot of evidence that humans use simulation Theory of Mind, which is an unconscious process for predicting other people, and also for predicting anything that behaves in a vaguely human way, which includes most animals. When I see another person, my brain automatically goes into Theory of Mind mode, so that instead of trying to predict them as if they were machinery, I put myself imaginatively into their place, set up a model of the world as I think they see it, then use my own response mechanisms to predict what they will do. This all happens unconsciously: I don’t think “I’ll imagine what it is like to be that person”, I just see them in terms of beliefs, desires, experiencing pain and so on. This unconscious Theory of Mind process works much better than trying to predict people as machinery, which is why it evolved. The same goes for e.g. looking at a rabbit: predicting it in terms of what it sees or hears, what it wants or is afraid of, works better than trying to predict how its neurons and muscles will react to events. We see people and rabbits as conscious because we predict them using an unconscious mechanism which involves putting ourselves in their place.


Interesting stuff. I recall reading about this process somewhere (it might have even been on this forum).

Plants generally react too slowly for the Theory of Mind process to be useful in predicting them, so (as I see it) we don’t think of them as conscious. Perhaps a time-lapse film of a plant root probing for nutrients might give the sense of awareness at work?


Perhaps. The main difficulty I have with these types of discussions is trying to get a grip on exactly what the "images" in my head are. Whatever it is, there's something going on there that I have difficulty extending to plants and many animals.

The other thing that bothers me about these discussions with Samsa, is the claim that all animals show similar levels of "intelligence" (I think that is how Samsa has described it in the past). That may be true, and I'm not trying to separate humans from the rest of nature, but clearly(?) there is something quite special going on in our heads that lower animals and plants don't experience. And that is abstraction and hypothesising about the future. I assume that this ability has played a large part in our outcompeting many of our competitors. I mean, why have such a large brain to body mass if it wasn't doing something very special? There may be other aspects of our physiology that have allowed us to ascend to the top of the heap so devastatingly, but I can't help but think our brains must have played the most significant part in that. So, to tie back to the issue of "intelligence", what is abstraction/hypothesising/memory/large-brain, if not "intelligence"?
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Re: Sentience in fish

#53  Postby Mr.Samsa » Jul 29, 2011 3:39 am

zoon wrote:
Mr.Samsa wrote:Is it possible that you're interpreting "consciousness" as "awareness"?

What distinction would you make between the two? The Oxford dictionary defines “conscious” as, first, “aware of and responding to one’s surroundings”.


The definition changes depending on what question you're asking, but generally all forms of the definition reduce down to "the ability to experience" - which is, of course, synonymous with 'sentient'. Only more advanced definitions of consciousness require awareness (since obviously it's possible to experience things without being aware of them).

zoon wrote:
Mr.Samsa wrote:
Firstly, I think I might have been unclear when I described the basic behavioral law that controls behavior. This is not a claim or belief of behaviorism, it is a conclusion from behavioral research. That is, Skinner didn't say "All behavior must or should be controlled by basic pain and pleasure principles". Instead, it just turns out that all behaviors that have been studied and understood have all been reducible to things like the matching law, or the contingency discriminability model. Essentially, all behaviors are reduced to choice theories because all behavior is choice behavior; so whenever you choose to do something (e.g. wave your arm around), you necessarily choose to refrain from doing something else. And all the currently available choice theories rely on "pain" and "pleasure" parameters.

A thermostat can be programmed to close a switch in response to a sensed temperature above a certain level (a heating mechanism is then closed and the thermostat cools). It would also be possible to program the thermostat to learn to close the switch, for example, if a light flash was followed on two occasions by a rise in temperature above the set level, the thermostat could be programmed to close the switch after any further light flashes, instead of waiting to sense the temperature going up.

If a thermostat was programmed to learn in that way, then presumably the thermostat, after learning from two or more light flashes followed by a rise in temperature, chooses the behaviour of closing the switch when the light flashes.


I'm not sure what you mean by "light flashes". Do you mean literally turning a flashlight on and off at a thermostat with some light sensor? If so, I don't see how this differs from kicking a rock and saying it has "learnt" to move away from a boot the moment it is touched.

zoon wrote:This would be because the thermostat has pleasure in a cool temperature and pain when the temperature gets too high? Someone who did not know anything about programming or thermostats might reach that conclusion, after observing its behaviour. And that method of predicting the thermostat would actually be correct, it would work – the thermostat acts to reduce temperatures above the set level, or when it’s learnt that the temperature is likely to go above the set level. Pragmatically, the thermostat would be correctly described as reacting to painful or pleasurable stimuli, and as learning.

However, for anyone who did know about thermostats and programming, the available theories would not be limited to reliance on “pain” and “pleasure”. There would be an alternative explanation for the thermostat’s behaviour in terms of electrical circuits and the properties of switches and heating mechanisms.


I don't think it would be possible to describe the thermostat's behavior in terms of "pleasure" and "pain". Obviously, as I mentioned earlier, I'm using those terms loosely to make conversation easier and they refer to more complicated variables, and importantly, the "pain" and "pleasure" are objectively defined and not inferred. For example, the thermostat's behavior would not be enough to attribute the label "pain" to it, as it does not exhibit the fundamental properties of what we define as a pain response - specifically, there are no avoidance or escape responses when presented with the aversive stimulus.

For example, if a significant rise in temperature was preceded by a slight rise in temperature 5 minutes earlier, then the thermostat should learn the first rise as a discriminative stimulus. As such, it should significantly reduce the temperature to counteract the future effects of a temperature rise.

If a thermostat could be designed to learn in this way, then not only have there been huge advances in AI, but I'd probably consider such a thing conscious.

zoon wrote:It seems to me that “pain” and “pleasure” are useful markers for ignorance, when we don’t know the physical mechanism for an animal’s behaviour (the mechanisms in even the simplest creatures like bacteria are fantastically complex and barely beginning to be understood).

When we use “pain” and “pleasure” as explanations, we are using Theory of Mind, which humans use more than other animals. We probably evolved it primarily to predict fellow humans, but it also works for predicting many non-human animals. If I say an animal, or a thermostat, acts in response to pain, then I’m putting myself in the place of the animal, or thermostat, and predicting what I would do. This all goes on unconsciously, I’m not deliberately pretending to be a thermostat, I’m just using my own action circuitry to predict what the thermostat will do, and it works.


I understand the point you're trying to make, but I'm using the scientific definitions which are necessarily true or not, with no need to infer mental states or invoke ToM.

rEvolutionist wrote:
Mr.Samsa wrote:You seem to be describing "sapience" here.


Probably. As I said, more "sapient" beings will have greater sense of potential loss, will have a greater understanding of what is happening to their fellow animals that are being killed for consumption. They're more likely to be able hypothesise about the future and potentially suffer more due to that. Would you agree that "suffering" would be greater for more sapient creatures?


Indeed - as I mentioned earlier, I think organisms with more advanced cognitive functions experience qualitatively and quantitatively more suffering.

rEvolutionist wrote:
There is nothing necessarily wrong with this, but it does fall into the trap Hugh describes above of valuing things which are human-like.


Why is that necessarily a "trap"? :ask:

As I said, I see no reason to attribute more or less importance or significance to this value system over another. And in a way it makes more sense, as it is the most relevant system for us to utilise as humans.


The trap is that it's essentially arbitrary - like defining alien life as having to be humanoid in shape, and then concluding that alien life doesn't exist even if we found a planet full of flora.

rEvolutionist wrote:
EDIT: I forgot to mention this, but plants don't just respond in a 'chemical/physiological' way (at least no more than animals). They actively employ methods to avoid pain, even without the painful stimulus present, etc. There is more complex learning and behavior involved in plants, and not just a simple cause-and-effect type response.


I didn't read Trewaras' (sp?) big paper, but read his shorter one in Nature. I can't say I was convinced by anything he said. Perhaps there was something extra in his big paper that wasn't in the shorter one? He didn't seem to give many examples in the shorter one, other than direct physiological reactions to stimulus (like growing towards light, or away from adverse soil conditions).


What about the ability to navigate a maze? If you track the responses of a rat with some kind of dye, and then watched the behavior of a plant on some time-series camera, you find that the routes taken are indistinguishable. (Also, his points of growing towards the light and aversion to soil conditions are more complex than how you seem to be presenting them - I do recommend reading his full article some time. I'm not saying he's right, and I don't agree with everything he says, but it's certainly an interesting perspective and I think at the very least he forces us to reconsider some of our understanding of plant behavior).

rEvolutionist wrote:
Behaviorism isn't a theory, it's a methodology. It can't be right or wrong in the same way "biology" can't be right or wrong. The only way it can be ignored or rejected is if it can be shown to be useless or unable to predict the subject matter it seeks to explain.


It's tenets could be wrong in the same way that biology's tenets could be wrong. But the underlying tenet of behaviourism - that behavioural organisms seek pleasure and avoid pain, is unchallengeable. There's no scenario that can be presented (well, that I can think of anyway) which couldn't be addressed by this tenet. Someone could naively say that those choosing suicide over life would be seeking pain and avoiding pleasure. But the obvious answer to this is that the person is seeking pleasure by avoiding the pain of life.


But as I mentioned below, that isn't a tenet of behaviorism at all (nevermind an underlying tenet). The basic claims of behaviorism are simply: a science of behavior is possible, mentalistic and anthropomorphic explanations should be avoided, circular explanations and explanatory fictions should be avoided, and cognitions can be studied and understood.

There is no specific requirement to understand behavior in terms of conditioning, or pleasure and pain, or anything. The fact that behavior IS understood in these terms is a result of overwhelming scientific evidence. That is, we wouldn't just say "the suicidal person is seeking pleasure by avoiding the pain of life", instead we'd experimentally test their responses to a number of conditions. Obviously this example is difficult since it's probably unethical to test a suicidal person in such a way that could encourage their behaviors, but what we'd do is put them in some setup which tested their response to "choosing life" and responses to "killing themselves" (I'm not sure how exactly this would be done), and then we'd take a couple of models of behavior to see which described the behavior the most accurately.

If a model that didn't include "pain" and "pleasure" explained it better, then we would reject all of those models as it has been disproved. (And, to clarify, I'm using "pain" and "pleasure" as very simple labels to describe more complex phenomena, but they're accurate enough I think to get the point across).

rEvolutionist wrote:I'm not saying anything about the veracity of Behaviourism here. I find it absolutely fascinating. Before I read what you had to say about it, I knew next to nothing about it. In fact, it seems the beautiful simplicity of it is its strongest point (i.e. it can effectively answer all questions about the act of living - at least at a general level).


I can't disagree with that :grin:

rEvolutionist wrote:
It's arguable whether it specifically comes from evolution. The behavioral law could be a natural consequence of having an organism that avoids bad things and approaches good things.


I don't get it? Surely "bad things" would have an evolutionary selection pressure?


Yes, I'm pretty sure the ability to experience "pleasure" and "pain" are a result of evolutionary pressures, however, this does not necessarily mean that the behavioral law that controls our behavior through these processes was specifically selected for. That is, the behavioral law could be a necessary derivation of these simple experiences.

As an analogy, imagine a river. The fixed parameters of the path it will take are: 1) gravity, and 2) the solidity of the surrounding ground (just keeping at these two factors for simplicity's sake). Now, just because those two factors are fixed does not mean that the resulting river was selected or designed by the mountain - it was a necessary consequence of the interaction of the two variables.

rEvolutionist wrote:
You mean on a neurological level? Long-term potentiation and in-vitro reinforcement appear to the mechanisms which control classical and operant conditioning.


I guess I'm asking how we scale up from say a tree root, or a simple animal, steering away from a negative stimulus, right up to humans abstracting and hypothesising about the future and behaving based on that seemingly immaterial stimulus.


It depends what question we're asking, i.e. whether we're asking if there's an absolute difference between humans and plants, or a relative one. On an absolute level, there is no difference between our responses and theirs (if we accept some of the examples given by Trewavas). But on a relative level, of course we differ. To paraphrase Darwin, the difference between animal and plant is one of degree, not kind.

rEvolutionist wrote:
How'd I do? :dopey: :lol:


Not good enough. :whistle: I want more info. I still don't fully appreciate what it is Behaviourism does and tells us.


Well behaviorism doesn't "tell us" anything, since it's just a methodology. But the results of sciences based on behaviorism tell us that the behavior of humans and animals can be described, understood and predicted using very simple laws. One of my entries to the science writing competition outlined in detail what behaviorism is: Misunderstanding Behaviorism, if you were interested.

rEvolutionist wrote:
Is it possible that you're interpreting "consciousness" as "awareness"?


I don't know. To continue my reasoning from above, I guess I think that "suffering" requires more than just simple "experience". It requires a deeper experience that implies some sort of understanding of sorts. i.e. Sapience, as you say above.


As I mentioned at the beginning of this thread, "suffering" (in science at least) is defined as experiencing a state of pain or aversion that is either high in intensity, or occurs over a prolonged period of time. Therefore, if something can experience pain, then it can suffer.

The question that I suppose you'd want to ask next would be: "Is this suffering worth worrying about, or should it be considered comparable to the suffering of other animals?".

rEvolutionist wrote:
Firstly, I think I might have been unclear when I described the basic behavioral law that controls behavior. This is not a claim or belief of behaviorism, it is a conclusion from behavioral research. That is, Skinner didn't say "All behavior must or should be controlled by basic pain and pleasure principles". Instead, it just turns out that all behaviors that have been studied and understood have all been reducible to things like the matching law, or the contingency discriminability model. Essentially, all behaviors are reduced to choice theories because all behavior is choice behavior; so whenever you choose to do something (e.g. wave your arm around), you necessarily choose to refrain from doing something else. And all the currently available choice theories rely on "pain" and "pleasure" parameters.


That's fine, I wasn't implying otherwise. It also doesn't change what I was saying.


You described it as an "underlying tenet of behaviorism" though? The point I was just trying to make is that describing it in such a way, is like saying an underlying tenet of biology was evolution. Evolution is obviously important to biology, but only because it's such an important finding backed by scientific data, not because it's an assumption of the field.

I appreciate that this is not what you intended to imply, but I just wanted to clarify it just in case.

rEvolutionist wrote:
Secondly, you're defining "variability" too narrowly. The "variable" in "adaptively variable behavior" simply means that the topography of a behavior can change in response to the same task or challenge. So if we put a rock in a maze, it's unlikely that it will find the cheese at the end. If we put a wind-up car in a maze, it's unlikely it will find the cheese at the end, etc, but if we put a rat in a maze, it will display a number of behaviors (e.g. 'go straight', 'turn left', 'turn right' etc) and this variability in behavior is adaptive (i.e. incorrect responses are extinguished, and correct ones are strengthened).


Yeah, I get what you are saying, but I guess it depends on the ability to separate variable movement out from an invariable "drive". As an example of what I am trying to say, think of a tree growing in part shade under other trees. There is an invariable goal "driving" its growth, and that is the need to get more sunlight on its leaves. But depending on other variables - herbivores, disease, wind, humidity etc. - it might display a different "behaviour" by growing towards a different area of higher light. But I wouldn't say this plant is showing variably adaptive learning. Perhaps this isn't the best analogy, as you might very well say that the plant is displaying this.

Meh, i've agonised over this paragraph for a while now and I just can't nail what I am trying to say. I'll leave it half out there, in case it prompts me at a later point to get to the crux of my problem.


I see what you're trying to get at in your 'erased' paragraph. You're trying to get at some notion of 'agency', in that whilst the plants behavior might have 'variability', you think this is just because other forces are pulling it around, rather than it 'choosing' one option over the other.

rEvolutionist wrote:Bloody pigeons. I'll never look at them the same ever again!


:lol:

Blip wrote:
Mr.Samsa wrote:Indeed - they are obviously tested with novel stimuli. The only way for them to solve the tests is for them to understand the abstract concepts behind the sample stimuli - the nature of grammar, or the style of a painter, etc. There have been numerous tests on musical discrimination, I'm not sure if any have compared Beethoven and Mozart, but here's a test of Bach and Stravinsky. They can also judge how 'good' or 'beautiful' a painting is. (And, if you're interested, here's a study on carp distinguishing between blues and classical music).

The grammar study is here, and followed up here Artificial Grammar Learning in Pigeons, and the statistics study: Are birds smarter than mathematicians? Pigeons (Columba livia) perform optimally on a version of the Monty Hall Dilemma.


Fascinating stuff, thank you. I'm predictably perturbed that the birds are kept markedly underweight in order to motivate them to take part, but that's for another discussion.


Don't worry, this is a common misreading of experimental procedure. The pigeons aren't kept underweight, they are on restricted feeding where they are kept at around 85% of their freefeeding weight. In other words, for a period of time they are given access to as much food as they like, and they pig out until they essentially reach their maximum size and weight. So it's like being taking to an all-you-can-eat for every meal of every day for about a month. Then we calculate 85% of this weight.

The end result is that they are within the correct weight range for what vets consider to be a healthy bird, and some approach the heavier end of this recommended weight. This means that they are far heavier than any wild bird, and generally fatter than any pet bird. In addition, the training sessions involve receiving food rewards, so they get plenty of food. So you don't have to worry about birds being "starved", as restricting their food actually means keeping them within the recommended weight range.

Blip wrote:I am not sure that, in the final analysis, these experiments don't simply reveal that pigeons can see and hear while fish can hear, which I knew already.


I'm not sure what you mean Blip? Seeing and hearing are not enough to solve these discrimination tasks. To discriminate between two classes of objects, the organism needs to develop a concept of what each class represents. Since they were tested using stimuli that they had never seen or heard before, then the only way to correctly complete the task is to identify elements of consistency between the two.

Blip wrote:I'm now wondering if my choice of the word 'sentient' was the best one: I'm used to choosing my words with care, but not in a scientific context. I suppose in the end it's the propensity for suffering that I'm seeking to establish, which takes us into the realms of consciousness, awareness and self-awareness (zoon and rEv speak of this above).

My own research in this area led me long ago to abjure intensively-reared animals (including fish - the sight of salmon trying to escape their captivity in fish farms would distress the hardest of hearts) but my current ethical dilemma is around eating wild fish.

Anyway, it's a fascinating discussion, that notwithstanding.


I suppose we can ignore all the scientific terminology for the moment and I'll just ask you one question: Do you think fish can feel pain? If so, then they must be able to suffer.

For me personally, it doesn't matter whether they have the cognitive functions necessary to contemplate their pain or awareness of their surroundings, but simply if it can experience pain then I'd want to avoid causing it unnecessary pain.

cavarka9 wrote:hello, sorry for interrupting,is it possible to have a condensed version of where people stand now. Do fish have sentience or not,


I still stand by the position that fish are sentient.

cavarka9 wrote:also we do have pigeons living in our balcony to raise their young-lings, they keep coming into our home, they probably know that we are not threatening.


:nod: They will be habituated to your presence, in the same way someone living in a big city becomes habituated to the sound of cars driving past and alarms going off.
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Re: Sentience in fish

#54  Postby rEvolutionist » Jul 29, 2011 4:14 am

Mr.Samsa wrote:
Blip wrote:I'm now wondering if my choice of the word 'sentient' was the best one: I'm used to choosing my words with care, but not in a scientific context. I suppose in the end it's the propensity for suffering that I'm seeking to establish, which takes us into the realms of consciousness, awareness and self-awareness (zoon and rEv speak of this above).

My own research in this area led me long ago to abjure intensively-reared animals (including fish - the sight of salmon trying to escape their captivity in fish farms would distress the hardest of hearts) but my current ethical dilemma is around eating wild fish.

Anyway, it's a fascinating discussion, that notwithstanding.


I suppose we can ignore all the scientific terminology for the moment and I'll just ask you one question: Do you think fish can feel pain? If so, then they must be able to suffer.

For me personally, it doesn't matter whether they have the cognitive functions necessary to contemplate their pain or awareness of their surroundings, but simply if it can experience pain then I'd want to avoid causing it unnecessary pain.


But there's a quantitative difference, surely? You could catch a fish in a net (level of pain probably quite small?) and then kill it quickly with an electric shock or a knife through the back of the head. So the fish may not actually experience much pain/suffering. What about it's buddies sitting in the net watching all this? Are they suffering from watching that initial fish's fate? Are they hypothesising and predicting the future and associating the fate of the first fish with their probable fates? Obviously I don't know the answer, but I'm guessing they don't to any significant extent. But higher order animals might and probably do to some extent experience more suffering due to the ability to abstract/hypothesise/predict based on events going on around them. This is why I am suggesting that the difference between sentience and sapience might be quite a critical distinction. I.e. sapient creatures can experience pain and suffering of their own imagining in addition to the pain received from us when capturing/killing them.
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Re: Sentience in fish

#55  Postby Mr.Samsa » Jul 29, 2011 4:23 am

rEvolutionist wrote:But there's a quantitative difference, surely?


I don't think so, not in the actual actions of those in the example below. Stabbing a fish in the back of the head would surely cause as much pain as stabbing a human in the back of the head?

rEvolutionist wrote:You could catch a fish in a net (level of pain probably quite small?) and then kill it quickly with an electric shock or a knife through the back of the head. So the fish may not actually experience much pain/suffering.


Indeed. I don't think any suffering occurs when animals are killed (properly), and I'm not aware of any animal welfare scientist that argues that they would suffer. Whether they feel pain in this instance, however, would be another question. I think they would feel some pain, but probably not too much, as you say.

rEvolutionist wrote:What about it's buddies sitting in the net watching all this? Are they suffering from watching that initial fish's fate? Are they hypothesising and predicting the future and associating the fate of the first fish with their probable fates? Obviously I don't know the answer, but I'm guessing they don't to any significant extent.


Hmm.. can't say for sure. If they have associated something like the smell of blood, or the electrical signals of an animals thrashing about, with a stressful event then arguably they could suffer from this. And since fish are incredibly good at social learning (i.e. watching and learning from how other fish behave), it could be possible that being placed in a stressful situation and seeing an example fish stop moving, could indicate something bad to them.

rEvolutionist wrote:But higher order animals might and probably do to some extent experience more suffering due to the ability to abstract/hypothesise/predict based on events going on around them. This is why I am suggesting that the difference between sentience and sapience might be quite a critical distinction. I.e. sapient creatures can experience pain and suffering of their own making in addition to the pain received from us when capturing/killing them.


Well fish can obviously abstract and predict future events, to a similar level as dolphins and rats and pigeons, etc.. If you're asking if fish know that when the big rubber gloves reach down and pull out their brother, whether they can tell he's going to die or not, then I'd say that's unlikely. Just as it's unlikely that a cow or a chimpanzee in the similar situation would know what's going to happen.
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Re: Sentience in fish

#56  Postby rEvolutionist » Jul 29, 2011 4:27 am

Hey? Surely Chimps and probably cows can pick up on the suffering of their compatriots? Perhaps you meant something else?
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Re: Sentience in fish

#57  Postby Mr.Samsa » Jul 29, 2011 4:31 am

rEvolutionist wrote:Hey? Surely Chimps and probably cows can pick up on the suffering of their compatriots? Perhaps you meant something else?


No more so than fish do.. But if you get a stun gun and zap a cow or a chimp so that it falls down in front of a conspecific, they won't freak out. They won't freak out when you reach down and slice their throats with a knife. However, given access to the dead animal, they will poke and prod it to try to figure out why it's not moving like it used to.
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Re: Sentience in fish

#58  Postby rEvolutionist » Jul 29, 2011 4:33 am

But what if the animal is stressed while it is being killed? Essentially in such a way that the surrounding animals were aware that it was in pain and being killed?
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Re: Sentience in fish

#59  Postby rEvolutionist » Jul 29, 2011 4:36 am

Mr.Samsa wrote:
rEvolutionist wrote:But higher order animals might and probably do to some extent experience more suffering due to the ability to abstract/hypothesise/predict based on events going on around them. This is why I am suggesting that the difference between sentience and sapience might be quite a critical distinction. I.e. sapient creatures can experience pain and suffering of their own making in addition to the pain received from us when capturing/killing them.


Well fish can obviously abstract and predict future events, to a similar level as dolphins and rats and pigeons, etc..


I actually missed this the first time through. I read that as "...fish can't...". That's interesting, and counter-intuitive to what I would have thought. What's the evidence underpinning this?
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Re: Sentience in fish

#60  Postby Mr.Samsa » Jul 29, 2011 5:04 am

rEvolutionist wrote:But what if the animal is stressed while it is being killed? Essentially in such a way that the surrounding animals were aware that it was in pain and being killed?


Then the observer animal would likely start to display behaviors akin to anxiousness and find the experience quite aversive. There would be no difference between fish, cows and chimps though.

rEvolutionist wrote:I actually missed this the first time through. I read that as "...fish can't...". That's interesting, and counter-intuitive to what I would have thought. What's the evidence underpinning this?


Well I linked to the study demonstrating their ability for abstract thought (by discriminating two musical styles), and the fact that fish can be conditioned to fear stimuli demonstrates that they have an understanding of future events, since a "conditional stimulus" is simply like a signpost that just indicates what is coming up (i.e. the stimulus doesn't take on the aversive properties itself). For example: http://www.sciencedaily.com/releases/20 ... 081908.htm

Given that there is no difference (that I know of) between the conditioning abilities of fish compared to dolphins, rats, or pigeons, then there's no reason to assume that any of those animals are better at it than fish.
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