So it is not obvious that our feeling of pain is universal.
Is that your argument?
This argument only works if pain and negative stimuli are the same thing.
And they trivially are not.
My argument is not "fish don't feel pain".
My argument is "proving fish dislike something is not enough to prove they feel pain".
For example, fish have been reasonably shown to feel pain by comparing their responses under painkillers to their natural responses.
Personally I don't think our experience of pain is universal, it'll be different with each combination of neurological and biochemical apparatus, but to me the idea that pain must somehow be proved rather than assumed in higher order is somewhat disturbing and indicitive of our continuing hunger for exceptionalism.
It doesn't disprove it, it just demolishes that particular argument.
> Animals don't respond in the same way to being prodded in the head as they do to being, say... eaten alive, so the existence of other forms of negative stimuli doesn't prevent you learning about pain responses.
That sounds like a good start to an argument, but "different" isn't to the point of "definitely pain".
> For example, fish have been reasonably shown to feel pain by comparing their responses under painkillers to their natural responses.
And that is also a good start to an argument, but "painkillers" have a lot of weird effects, so it needs more work.
But neither of those is related to geezerjay's over-simplistic argument.
> to me the idea that pain must somehow be proved rather than assumed in higher order is somewhat disturbing and indicitive of our continuing hunger for exceptionalism
I'm not sure exceptionalism is the right word, considering how broad the category of "clearly feels pain" is.
But I'll remind you there are certain humans with a mutation that makes them unable to feel pain, while mostly leaving their other senses intact. And naked mole rats have a vastly different and muted pain response from their relatives. It's completely plausible to say that an animal might not experience pain.
geezerjay made the point that the ability to experience pain is a useful survival trait, so we should expect it to be widespread.
Filling in some gaps in your argument (please correct me if I get them wrong), you're arguing that there are other negative stimuli that could have equivalent usefulness and therefore pain itself is not beneficial for optimising survival. Any equivalent stimulus would do.
Since there's no way to tell what anyone feels, the entire subjective experience of pain can only be defined by looking at analogous physiology and response. We can look at things like whether a species has nociception, whether their nociception system interacts with their central nervous system, whether they respond to painkillers, how they make choices about negative stimuli, adaptive avoidance, etc.
To have the same survival value, your 'negative stimuli' must be indistinguishable from pain. They have to be because you imply they illicit the same response in the same situation, and (barring species that are clearly missing key parts of nociception) the response is all we can look at.
Your argument seems to rest on redefining the (admittedly vague) biological understanding of pain to mean a unspecified subset of 'things that are indistiguishable from pain'... which I don't buy as being anything other than an existential conundrum and in my opinion doesn't seem like a basis to call geezerjay's comment "over-simplistic".
While also conflating "pain" with any negative reaction at all as a "basic survival tool".
> Filling in some gaps in your argument (please correct me if I get them wrong), you're arguing that there are other negative stimuli that could have equivalent usefulness and therefore pain itself is not beneficial for optimising survival. Any equivalent stimulus would do.
I wouldn't say "equivalent". But I would say "sufficient".
So go ahead and throw out all your argument based on them being indistinguishable. They are distinguishable, but it can be hard to distinguish them in something that doesn't talk.
Keep in mind that we already know from daily experience that multiple kinds of negative stimuli exist, and only some of them are painful. Suppose that having more types requires more complexity, more metabolic energy. In that case, in simpler organisms, it could easily be true that pain improves survival but the cost is greater than the benefit. And then pain would get evolutionarily selected against despite being useful.
And that assumes that pain is better than not-pain to start with. Maybe pain is a kludge. A lot of deaths have been caused because pain got too overwhelming for someone to continue to escape/fight.
> We can look at things like whether a species has nociception, whether their nociception system interacts with their central nervous system, whether they respond to painkillers, how they make choices about negative stimuli, adaptive avoidance, etc.
Yes, this is a good starting point. They key is acknowledging that there are multiple ways to get reactions, and pain is only one of them, so we have to have finesse in figuring out whether or not pain is involved.
You're right, there could exist a tier of organisms that do have centrally nervous nociception etc. but don't feel "pain", depending on which set of criteria you use to define what is and isn't pain (you didn't say which of the competing sets of criteria you subscribe to).
As far as I see it, geezerjay put forward a reasonable argument and this adds a possible (but so far unsupported) nuance.
It doesn't matter what my exact definition is for pain as long as we can agree that there is a difference.
(We can agree that soft pokes to the head don't hurt, right?)
And because there is a difference, it's not nuance to say "You can show that avoidance of stimuli is nearly universal, but that's not good enough to show pain". Without that equivalence, the argument is half-finished or less.
Plants respond to anesthetics, some can react to touch/electricity/heat with rapid movement(thigmonasty), they can sense when they are being damaged, some can even display short-term memory.
But do they feel pain? They have no pain receptors. They have no nervous system. They can feel pressure/vibrations, and even respond to it, but that's it.
I feel that we should presume consciousness, pain, emotions, etc, in all living beings, until most rigorously proven otherwise, because just because we may not understand non-human, non-mammalian or non-animal living beings as well as ourselves does not mean that they cannot experience whatever equivalents their consciousness, bodies or minds allow them to.
My argument is that all living things can feel pain, regardless of how it manifests for them.
Eating animals is trickier. You’re eating processed plants, so you’re still harming plants by eating them, but you’re harming an order of magnitude more plants (due to the inefficient conversion from plant to meat), and you’re harming animals as well. There’s therefore a very strong argument to be made that eating meat is immoral.
However, I'm criticizing the article because it suggests that previously the scientific consensus was that terrestrial vertebrates did feel pain while fish did not. I seriously doubt such a consensus existed...
Regardless of whether or not an entity X experiences pain, we can still objectively state that entity X responds negatively towards stimuli associated with the feeling of pain in ourselves.
You can (and should) argue with brain structures - however, this can lead you into the trap of assuming that less is going on than actually is. People mistakenly assumed that birds are incapable of reasoning and cognition because they don't have anything resembling a cerebral cortex. Today we know they do have brain structures for reasoning - they are just organized completely different than in our brains.
However even that does not apply to fish - the main argument of the article was that the majority of research actually did find the same brain structures in fish that would handle pain in humans, along with matching neuronal activation patterns and matching behaviors.
So I think if the level of evidence is as the article describes, the old adage applies: If it walks like a duck and quacks like a duck, it's probably a duck.
The situation here is more like: if it looks like duck and created/evolved for attracting ducks, it's probably a duck or a duck decoy.
While evolutionary value of pain response is clear, evolutionary value of suffering is not.
There is apparently a lot of evidence that the neural activities that underly the experience of pain in humans happen in much the same way in fish. No matter why this is so, it makes the hypothesis that fish do feel pain more reasonable than the opposite.
Do those reasons remain equally plausible for K- and r-selected species?
> it makes the hypothesis that fish do feel pain more reasonable than the opposite.
Yes, conditional probability of fish feeling pain given the existence of similar brain activity patterns is higher than otherwise.
It doesn't mean that further research can't lower that probability. Like finding more similarities of fish brain processes with brain processes of people who don't feel pain.
What do parenting strategies have to do with any of this? (If I understand wikipedia correctly)
> It doesn't mean that further research can't lower that probability. Like finding more similarities of fish brain processes with brain processes of people who don't feel pain.
That can always happen, with any kind of research. I don't see how this gives any reason to assume today that fish don't feel pain.
I know I feel pain. I don't know anything about your experience of pain.
That seems like the distinction between reliably identifying the colour red, and the qualia of red. I don't know that they are different things in any way we can understand.
There is no difference between identifying the colour "red" and the qualia of it, because we must directly know the latter to do the former. It cannot be described, understood nor appreciated without first having the direct experience.
What I mean is: unless you have some privileged information about where consciousness and qualia come from, how can you tell whether or not measurement machinery perceive qualia?
(I've thought about this for a long time myself, and I don't know where to draw the line, so I drew it differently: everything is "conscious"; i.e. panpsychism.)
Otherwise all the agency and supposed consciousness comes from outside of the system (e.g. from out empathy) and is not an inherent part of the system.
How are they different? Pain is a negative stimulus response that allows us to know whether something is causing damage to our body.
> We know we feel pain. We can guess that organisms with similar brain architectures are feeling pain.
How does feeling pain have anything to do with a brain's architecture? It has more to do with nerves... block a nerve's functioning, and you don't feel pain. Also, pain can be psychosomatic.
> Ants keep doing their job even after fatal damage. If they feel something, it is not anything like our pain.
Have you seen ants writhe around after being crushed or dismembered? They definitely feel pain.
> So it is not obvious that our feeling of pain is universal.
Depends on your definition of pain, doesn't it?
Direct link from a receptor to an effector is sufficient for negative stimulus reaction. But it is not sufficient for pain. Rapid withdrawal of a limb from a hot object happens before we feel pain.
I always feel pain in that instant. I feel the pain before I can even consciously react to it, because of the shock from it. Unless of course the nerves are shocked enough to prevent the pain from being felt immediately.
Heat/burning sensations use the slowest type of nerve fiber, only moving at .5 to 2 meters per second. While the primary actors related to movement are at 100 meters per second.
The difference is between the unpleasant, subjective experience (qualia) and the electrical signals indicating physical damage.
A car has sensors that detect physical damage, yet it doesn't feel pain in the way that humans do. The question is, where on that spectrum bacteria, ants, and fish lie.
> Have you seen ants writhe around after being crushed or dismembered? They definitely feel pain.
Have you seen a car deploy its airbags and notify emergency services after a crash? And yet, they definitely don't feel pain. Visible reaction to a negative stimulus is neither a sufficient nor a necessary precondition for someone or something to feel pain.
Event plants, bacteria, and amoebas? You sound very sure – how do you know this?
Animals have consciousness and can feel pain. Animal and plant bodies are both comprised of many differentiated cells. Both have DNA. Bacteria are singular cells, and have DNA...
Plants have been demonstrated to have short-term memory, recognize family and neighbouring plants, and so on. So... it is extremely likely that plants, bacteria, fungi, and perhaps even amoebas, also have consciousness, feel emotions and feel pain. Maybe not in the way we think about emotions and pain, but in whatever way they do, which is entirely mysterious to us, being animals with animal-consciousness and instincts. We cannot understand what it is like to be a plant, bacterium, fungus or amoeba... it is far too alien to our animal-mind.
You may find these articles of interest:
http://www.naturaltherapycenter.com/the-secret-life-of-plant...
https://nautil.us/issue/34/adaptation/junk-food-is-bad-for-p...
Malfunctioning limbs will cause the same effect. Ant without a gaster will continue to function normally.