Philosophical Vegan Forum

Read the full article for complete context. I'll cite a few parts for the basic info here.
http://veganstrategist.org/2016/11/03/go-post-vegan/

tobiasleenaert wrote:Whenever there’s an issue of some complexity, there is, so to speak, a pre-consideration stage and a post-consideration stage. [...]
Often, or even most of the time, the beliefs in the pre-consideration and the post-consideration stages will look radically different. But sometimes, interestingly, they are or appear the same. [...]
Let’s look at an example to see this more clearly. Imagine that you are someone who is very skeptical about GMOs (you’re boycotting GMO products, maybe attend anti-GMO protests, etc). When you meet a person who’s not bothering about GMOs at all, you may assume that they are in the pre-consideration stage: you believe they don’t know much about the GMO issue, don’t know about the supposed dangers of it, haven’t educated themselves about it, and therefore are just eating and buying anything, independent of whether the product has GMO ingredients or not. This person, however, may be doing what they are doing (which is being indiscriminate and indifferent about GMOs), because they are well informed about it and have given the issue a lot of thought. In other words, they are in the post-consideration stage (who knew?!). Their behavior looks the same, but their beliefs and intentions are entirely different.

What this means, in short, is that we may easily mistake someone who’s in the post-consideration stage (on a certain issue) for someone who’s in the pre-consideration stage. While we think they are behind us in their thinking, they may actually be ahead of us – meaning they have thought about and researched the issue more than we have (without this implying that they are necessarily right and we are wrong).

Now, let’s look at how this applies to veganism and vegan advocacy. Here too, we can find statements, behaviors, attitudes, beliefs… that at first sight seem to be part of the pre-consideration stage, but could as well be demonstrated or voiced by people in the post-consideration stage.

Take, for instance, many of the objections from omnivores that vegans usually refer to as unthoughtful (to use a polite term). You’ve heard them all before:

– “Isn’t being 100% vegan extreme?”
– “What would you do if someone offered you a lot of money to eat a steak?”
– “What if plants feel pain?”
– “In the wild, animals kill each other, too.”

I basically agree with the others as Tobias reinterprets them, this is the one I want to get at here:

tobiasleenaert wrote: But can you imagine that these statements actually could come from thoughtful people, including vegans, who have given serious consideration to these issues? Let’s re-interpret them in that way:[...]
"What if plants feel pain?”
Again, we usually think this is a stupid gotcha, but at the same time, it’s a perfectly sensible question. We’ve been wrong about the cognitive capacities of other species before; so, is it not at least possible that we are wrong in the case of plants, too? If we are wrong, what are the consequences? (It’s definitely an interesting question to ponder.)

I can not imagine that question coming from somebody both thoughtful and well informed on the issue.

I think any question can be serious, if somebody has gotten wrong information. Reports on plant intelligence/sentience/consciousness are headline grabbing yellow journalism (its exaggeration and misapplication of terms), and yet I can understand why some people will consider them credible, just as people may think there's serious skepticism on climate change due to the media they are exposed to. This is not well informed, though. Neither is it careful introspection.

By post consideration, I take it to mean that the person was really well informed on the issue and might conceivably be right, requiring serious and considered discussion, as opposed to being in need of information and correction.

The thing is, awareness or pain isn't just sensing ability, which plants have, but the capacity to understand and meaningfully experience that sensation (at least, it implies this).
Plants are aware in the way that your skin is, as it reacts to light by tanning, or in the way your immune system is; it's purely reflexive in terms of its responses. Even the way of a computer doing word processing is; it senses the input from the keys and responds, but at no point is it really aware of what you're doing, and pressing the delete key can't really be painful. It's not a conscious awareness or sentience.

A more valuable question is whether the line we draw between plants and animals is arbitrary (which is sort of what the question is trying to ask), and to that I think a post-consideration answer is yes.
Sponges, oysters, jellyfish, some worms, plankton, maybe even certain insects: why do we consider these to have moral value? Why do we not eat them? That's a difficult question for vegans to answer.

The line of sentience seems to be so far into animal territory, that to me it seems like -- or worse than -- asking if our electronic toys or cellphones or cars feel pain; devices that frequently have sensors coupled with more information processing power than plants. Is the check engine light on a car a cry of distress and suffering? The car has certainly thought about it far more than any plant does when it reflexively releases alarm pheromones upon cell damage.
Even more comparable, how about asking if baking soda experiences pain when vinegar is poured on it, because it reacts in such a way?

Just because something reacts to stimuli in a certain way does not mean it feels -- and this is an important post consideration realization that brings lower animals into consideration rather than changing the way we should think about plants.

Asking what if plants feel pain is much like asking what if cows chickens dogs and cats don't feel pain; it's quite far beyond the kind of questions being informed and considered on a topic would generate, knowing that current uncertainty and investigation on the ethics of experimentation without sedation/etc. is around fish (at most) and things like insects and worms (in the least and most extreme).

My point, as it relates to activism and the purpose of the original post, is that "what if plants feel pain?" is a clear indication of a pre-consideration mindset. It indicates a person who needs more information, or needs correction on wrong information (I've been pretty successful at diverting this question to one of which animals don't feel pain instead; people understand gradients, they just need to learn that the line of consideration is much farther into animals rather than around plants).
To better inform veganism (post-veganism), "what if plants feel pain" is just the wrong question to ask, and it takes us in the wrong direction or distracts from an important issue. Instead, we should be asking where the line is, and which animals don't feel pain/aren't sentient or conscious.

thanks for the topic
i feel that i, as a thinking person, can still ask the hypothetical "what if plants feel pain", from a place of genuine intellectual curiosity (like, what would that imply, what would we have to do if that were the case?), as contrasted with the "gotcha"-attempt of the resistant omnivore.
any hypothetical is valid, i think (note that it's the only hypothetical in the list)

btw, (off topic) another example of where i myself have evolved (one could say full circle, but i don't know if that entirely covers it) is the topic of suffering:

stage x: i don't care about animal suffering
stage x+1: **animal suffering is important**, but animal rights is extreme
stage x+2: we're not about suffering, we're about *rights*!
stage x+3: **animal suffering is important**

I agree with Brimstone's assessment of the question of plant sentience; that it is a sign of ignorance, even if not intellectual dishonesty, which is a sign that the person that poses the question is in the pre-consideration stage.

I found tje article very interesting nonetheless. Tobias makes a good point that it is important to recognise that one can be in the post-consideration stage and still disagree with us. Such a person probably raises the need for a different approach than somebody in the pre-consideration stage.

PS, thank you for the reading list om your site, (and Brimstone for linking to it) I'm really enjoying Made To Stick and Influence is next.

tobiasleenaert wrote:thanks for the topic
i feel that i, as a thinking person, can still ask the hypothetical "what if plants feel pain", from a place of genuine intellectual curiosity (like, what would that imply, what would we have to do if that were the case?), as contrasted with the "gotcha"-attempt of the resistant omnivore.
any hypothetical is valid, i think (note that it's the only hypothetical in the list)

The danger of asking a hypothetical question like that, at least publicly, is that it an confuse people and lead them to believe it's a real possibility, or that it's something at least plausible that we need to be wary of.

It also quickly goes off the rails...
If plants actually felt pain in what that implies, that would mean sentience and consciousness which exist without the structural and information processing foundations, which would suggest that, for lack of a better word, plants have some kind of soul or spirit in them. And at that point, we have to ask if rocks and mountains, the wind, the ocean, and rivers, too, are sentient and feel pain. We'd pretty much have to throw out all of material science to ask about the experiences of ghosts, and even the consequences of sin on the experiences of souls in life after death.

If we lose the natural sciences and material reality as a grounding for ethical thought, we're thrown a bit to the wind.

Best case, thought experiments like these are a fun pass time along side 20 questions and Carcassonne, worse case they cause harm by distracting from more plausible lines of questioning and even confuse people. I just don't think that it's a road that leads anywhere that's really productive to vegan activism.

tobiasleenaert wrote:btw, (off topic) another example of where i myself have evolved (one could say full circle, but i don't know if that entirely covers it) is the topic of suffering:

stage x: i don't care about animal suffering
stage x+1: **animal suffering is important**, but animal rights is extreme
stage x+2: we're not about suffering, we're about *rights*!
stage x+3: **animal suffering is important**

I think many here went through that. I could see stages of consideration on pain and sentience somewhat mirroring that too.

stage x: Only humans experience pain/don't care
stage x+1: Animals experience pain, plants don't
stage x+2: Maybe plants experience pain too?
stage x+3: Plants can't experience pain, but many small/simple animals can't either, the line is not as clear as Kingdom.

The question of which things can suffer, and so require ethical consideration, is a very interesting one, as it really comes down to the question of how subjective experiences are generated by physical systems. We have good reasons to believe that our consciousness is produced by our brain, but it’s a complete mystery how that happens (this is the ‘hard problem’ of consciousness). We know that animals have nervous systems which have varying degrees of similarity to ours, and we also see behavioral evidence that (most) animals feel pain, so we have very good evidence that (most) animals do feel pain and, importantly, that they suffer from it. But it does remain possible that there are other physical systems apart from nervous systems that can also generate subjective experiences such as pain. I believe some philosophers are even starting to seriously consider the possibility that artificial intelligence might one day acquire sufficient consciousness that we need to consider it ethically (although this seems like science fiction still to me). As for plants, we can’t be certain that plants don’t feel pain, by using some mechanism other than a nervous system. That’s also true for rocks, but the fact that plants are living organisms and rocks are not means that some people might consider the question of plant consciousness a more serious question that rock consciousness.

I have no doubts that when the subject of plant consciousness is raised in relation to veganism, it is pretty much always a defensive and not well thought out argument by people trying to justify eating animals, so I can see the reasons for not discussing this subject in the context of vegan advocacy, for fear of fueling further bad thinking. But as for the hypothetical question of what if plants do feel pain, isn’t it true that an omnivorous diet results in more plant death than a vegan diet, because of all the plants needed to feed the animals? So even if plants did feel pain to the same extent as animals, doesn’t that still mean that a vegan diet is the more ethical one?

I believe it is around 14% of people who actually believe in bigfoot. Now, of those people, several are actually extremely well informed in all aspects of bigfootology. Some are even scientist who are otherwise respected in their fields. Much like religious scientist, they understand the information available, but for one reason or another choose to interpret it differently.

Now this is a small percentage, but I agree with him that this could actually be a post-consideration mindset for many. There is no argument, however valid and insightful, that will sway them otherwise.

As much as we would like to believe that everyone is capable of rational reasoning(as we see it) if only we explain it in a way that they understand, sadly, this is not true. By accepting this reality, we could learn to spend less time and stress trying to persuade the bigfooters, and more time focusing on the bigfoot-curious.

I don't think plants "feel" pain. And I don't think any of the evidence for this that we have so far is remotely convincing.

However, I am not willing to exclude the possibility that plants *might* feel pain. They *might* even be subjects of a form of experience/sentience that we simply cannot comprehend (the same is true of bacteria, however unlikely).

But I also believe we have the right to survive as a species, and we need food for that. And we kill fewer plants by eating them directly than if we were to feed them to animals and then eat the animals.

So, napalming the jungle is kind of dumb however you look at it. But eating plants is necessary at this point in time, and I wonder how meat-eaters ever thought this was a reasonable argument against veganism in the first place.

ModVegan wrote: However, I am not willing to exclude the possibility that plants *might* feel pain. They *might* even be subjects of a form of experience/sentience that we simply cannot comprehend (the same is true of bacteria, however unlikely).

I don't understand this argument. Why wouldn't you exclude these things?

Would you not exclude the idea of rocks, or water molecules, being sentient? It's in the same realm of plausibility. Would you not exclude hard solipsism and the idea that other human beings are not sentient?
The problem is that once you open the door and consider potentially credible certain ideas, pretty much anything can get in, and in these ponderings we lose touch with reality.

Here's what I mean:

ModVegan wrote:and we need food for that.

But bretharianism is at least as credible as plant sentience. How can you rule that out?
Or maybe people have to eat meat, despite all evidence to the contrary (just as plausible). If science is wrong about plant sentience, maybe it's wrong about humans being capable of being vegan.
Or maybe plants are sentient but their sentience lies in their roots and is protected from grazing cows but not from plowing humans, and in addition cows are non-sentient (or even like to be eaten) thus grass fed meat causes less harm?

These hypotheticals get totally out of hand when we permit the discussion to cut all ties to reality. There's no reason we need to go on this hypothetical journey with carnists. If somebody is that committed to believing alternate facts, what stops them from adding one more in, changing the rules a little more in the middle of the game, and declaring checkmate yet again?

Also:

ModVegan wrote:But I also believe we have the right to survive as a species,

Why do we have the right? Where does it come from and who gave it to us? What reasoning leads to this conclusion?

On the same basis people could claim that plants have the right to survive on not be eaten (another assertion with equal backing). Or that cows (as a breed) have the right to survive, even if that means we have to keep farming them -- even that we are obligated to do so.

ModVegan wrote:So, napalming the jungle is kind of dumb however you look at it. But eating plants is necessary at this point in time, and I wonder how meat-eaters ever thought this was a reasonable argument against veganism in the first place.

Kind of a false dichotomy.
You could be a fruitarian, and eat only what falls from the tree/bush/vine/etc.
If we're forced to consider the moral harm we do to plants, there's a lot more we still could do. It would be pretty extreme, but not impossible, and it just gives credence to the carnists' slippery slope arguments.

brimstoneSalad wrote: Would you not exclude the idea of rocks, or water molecules, being sentient? It's in the same realm of plausibility. Would you not exclude hard solipsism and the idea that other human beings are not sentient?
The problem is that once you open the door and consider potentially credible certain ideas, pretty much anything can get in, and in these ponderings we lose touch with reality.

These are ridiculous straw man arguments, sorry. I'm discussing the possibility that plants - biological organism which have complex interconnected systems designed for communication, etc., have a form of sentience/awareness we may not be able to comprehend given our current knowledge. You jump to breatharianism? We have direct evidence organisms require fuel for survival. We also know that plants exhibit signs of nociception. I fail to see the relevance of this argument.

brimstoneSalad wrote:On the same basis people could claim that plants have the right to survive on not be eaten (another assertion with equal backing). Or that cows (as a breed) have the right to survive, even if that means we have to keep farming them -- even that we are obligated to do so.

[/quote]

Self-preservation is a natural instinct I don't expect any living thing (plants, animals, etc) to rise above. To call it a right may be excessive, but it is certainly a reality. I'm not going to hold a survival instinct against any organism, unless our needs come into conflict, in which case I'm likely to use any tools available to me to ensure I come out alive and well. But acknowledging self-preservation as an instinct is a far cry from saying we're required to keep breeding cows to preserve their species for them.

Plant Neurobiologists like Stefano Mancuso are serious scientists. They aren't asking anyone to become fruitarians, they are simply interested in understanding plants better and answering questions like, "what's the best way to plant trees?" I would venture to say that 99/100 times, this argument is not brought up with any sincerity, but I have no problem discussing it with non-vegans if they are asking genuine questions.

Plants clearly have some experience of the world, though the absence of a central nervous system means it would be on a level completely unintelligible to us (at least at this point). I fail to see the value in belittling that.

ModVegan wrote: These are ridiculous straw man arguments, sorry.

They aren't, though. You may believe they are, but do you really know what consciousness is? Do you know what sentience is? How about intelligence? In the technical sense, in terms of behavioral psychology and the most recent research in the relevant scientific fields?
You even mentioned bacteria. Do you understand how small these things are? Do you know about quantum mechanical limits? Thermodynamic limits?

We're talking about information systems here. There's a certain amount of computation that has to go on to create a robust enough network to model the outside world and to learn in any meaningful way. There are minimum system requirements.

It's as if you said that's it's possible for Windows 10 to be installed on a digital watch from the 70's.
No, it just isn't. It's not any more likely that you'll be able to run it on that than you'd be able to run it on a jar of pickles. That's not a straw man. The probability in both cases is zero. Both contain silicon, but both are woefully lacking in basic system requirements. The distinction in terms of the probability of them being able to run windows is not meaningful; the only way they "run it" is if you tape a modern Windows phone to them or somehow make them part of a larger computer system.

If you had no idea what Windows was, or any idea of the capabilities of the first digital watches four decades ago, the idea that maybe a 1975 digital watch could run it could seem plausible. But it's an argument from ignorance.
You assume it's possible because you don't know enough about it to understand why it's impossible.

It's perfectly fine to not know and to be honest about that. But the problem comes when you say it in a way that implies that people who say they DO know are somehow closed minded or dismissing realistic possibilities. Or accuse them of fallacies.
Can you see how that's kind of insulting to people who have devoted a considerable amount of time and energy to studying the topic and trying to stay up to date on it?

(Despite feeling a bit insulted, I'm going to spend a lot of time explaining why you're wrong instead of saying it's "beneath contempt" and then running away. )

ModVegan wrote: I'm discussing the possibility that plants - biological organism

That they are biological is not relevant. There are arguably sentient computer simulations and Synthetic intelligence. Mineral and crystalline systems in rocks can be highly developed (may even be the origin of life), and the interplay of fields at the subatomic level can be astounding; we can't even simulate most of this stuff properly on supercomputers yet.

The first questions you should ask is whether they have the prerequisite information storage and processing capability to to run sentience 1.0, and in the case of plants, bacteria, rocks, and water molecules, the answer is "No" they do not.

If it's at least conceivable, as perhaps in the case of oysters where there are some nerve clusters, we then have to look to other indications like behavior, and even to usefulness: is it evolutionarily useful for oysters to be intelligent? Does sentience serve them in some way? Bear in mind that intelligence is extremely expensive, metabolically, so it has to be worth it; animals do not typically have brains larger than they need to get the minimum job of procreating (and providing for offspring to do similarly) done more often than dying first.

ModVegan wrote: which have complex interconnected systems designed for communication, etc.,

First, this verges on circular reasoning; communication implies understanding. Plants are not really communicating (no more than is one rock "communicating" temperature information to another rock by conducting heat, or one domino communicates to the next one in a row that it's time to fall with a gentle tap), and they weren't designed to do it; it's an 'accident' of evolution that usually works better than it hinders the plants.
When we use language like that, the topic can get loaded really quickly with implications of intelligence, and that will lead you astray.

The systems are far from complex; it's just an interplay of hormones that trigger or repress gene expression, which is programmed in. The only thing that makes them opaque is that they're kind of hard to study. It's entirely mechanical, not intelligent; horticulturalists take advantage of them constantly. Like when you cut a higher stem it can trigger the lower buds to grow because you've removed the source of hormones preventing them from doing so. It's not that they've been told or decided to grow, it's that mechanically that hormone suppresses growth, and mechanically, it originated from another stem.

It's a very elegant emergent solution to the problem of regulating plant growth, but it's not intelligence. It's physical in nature, there is no information processing or understanding, it's just the push and pull of competing hormones. Compared to actual intelligence it's crude in a way, but it works and it's metabolically far cheaper than having intelligence thinking about and deciding things.
Understanding how these systems really work shouldn't take the magic out of them by making them less mysterious, it should be all the more beautiful. But we shouldn't mistake beauty for intelligence or sentience.

The problem with the transmission of information in a plant, as with a rock, is that it's not discriminating; it's more of a diffusion. You don't get a letter with a to and from, the cell (which is the only unit that really matters) just gets bathed in hormones which turn off or on genes and make it react in a predetermined way.
A leaf does not know that a chemical is coming from another plant or another leaf on the same plant, and it does not care or understand what it means. The response is reflex. And the sender, likewise, has no idea where that hormone is going and no way to direct it to any particular destination.
This kind of transmission makes any meaningful information processing very difficult because it makes elaborate structural systems impossible.

It's a little hard to explain unless you have some background in computer science. Do you know anything about logic gates?
Here's a site that explains a bit: http://www.explainthatstuff.com/logicgates.html
(You really need to know the basics of computer science and digital electronics in order to deal with the concepts)

Computers are built from them, and the reason is works is that the input from one is fed directly into others in a particular controlled sequence. If you take that away, and try to build a computer by diffusing input and output, you make it basically impossible to build anything useful.
A plant has multiple hormones, but ultimately it only gets as many signal channels as it has hormones (which is a small number), or else those signals will interfere with each other. Think multiple radio stations trying to use the same frequency. It doesn't work, any useful signal gets lost in the noise. In different cities they can do it, but not locally.

In order to form an information processing system necessary for true intelligence, consciousness, and sentience, you need to be able to channel those outputs to a particular cell or cells which will reprocess them based on other inputs, then provides a different output, and so on and so forth to a certain minimum system size that it becomes capable of generating conscious experience by letting the reactions and structures change themselves.
This is why our nerves are connected as such with insulated transmission lines to prevent signal loss or noise creation for other nearby neurons. The structural capacity to do this is lacking in plants and bacterium.

There are SO many reasons they're not sentient. This is just scratching the surface.

ModVegan wrote: have a form of sentience/awareness we may not be able to comprehend given our current knowledge.

I really hope after reading the above you see how silly (and insulting) this kind of claim is.
This is a textbook woo claim, I'm sure you've seen people say this kind of stuff about altmed or crystals or whatever too.
"Maybe homeopathy/reiki/whatever bullshit etc. just works in ways we may not be able to comprehend given our current knoweldge."
No. Even if we don't understand every detail of how everything works, the unknowns are not vast enough to drive that kind of megatanker through the gaps.

This is literally an argument from ignorance. You're insulting the state of our scientific knowledge, denigrating entire fields as ignorant and dismissing generations of work as having nothing to say on the matter, and on what basis?

Your assertion is that we just don't know anything about it -- but you're speaking for everybody else too when you do this, you're speaking for all of science, and not just for yourself. If you said only that you didn't know, that would be fine. When you say that I (right here on the other side of the internet from you) don't know, that's a problem, because you don't know what I do or don't know, and when you say that nobody knows, that's even worse.

The same can be witnessed in militant agnosticism.
Run of the mill agnosticism -- great, you don't know, I can respect that. Totally cool, maybe let me explain it to you so you can be more informed and catch up a bit of what you might have missed?
Militant agnosticism -- nobody knows? Really? In the whole world, you can't conceive of anybody possibly having access to information or some logical argument you haven't heard? And you're certain of that? That's a statement of faith every bit as profound as the Pope's.

In order to be honest, we have to temper our certainty, but we also have to temper our certainty about uncertainty. There are some things that are just so far beyond plausible that it is not reasonable to take them seriously.

As the saying goes: "keep an open mind, but not so open your brain falls out."

ModVegan wrote: You jump to breatharianism? We have direct evidence organisms require fuel for survival.

We have direct evidence that organisms require fuel for intelligence; huge amounts of it. And we have direct evidence that information processing is a function of the cells doing the processing and the channels they can use to transmit input and output. This is pretty hard core physics and mathematics.

The best case you're likely to ever find are limited cases of plants that are highly invested in motor function, like the 20 second "memory" in the sensing hairs on a venus fly trap. This is not intelligence, and it's not capable of supporting intelligence. Maybe given a few more hundred million years of evolutionary pressure, but not in its current niche.

If you can casually dismiss information theory, thermodynamics, and evolutionary biology, then I can dismiss just one of those things with bretharianism. Both assertions are wrong, but the possibility of bretharianism violates fewer fundamental laws of physics and logic.

ModVegan wrote:We also know that plants exhibit signs of nociception. I fail to see the relevance of this argument.

We do? Are you sure about that? http://medical-dictionary.thefreedictionary.com/nociception
Do we also know that plants are psychic, and possess ESP? http://skepdic.com/plants.html
(Read the whole article and you'll see where a lot of this nonsense came from).

Plant cells automatically release a cascade of hormones in response to damage, and those affect gene expression locally and in the whole plant (and even in nearby plants). They do not feel pain. They do not have animal nociception, although some hormones are similar, that's more coincidence; we see hormones with estrogen-like activity from plants too.

The problem is so bad with these poor comparisons to neuroscience that a few years ago a bunch of plant scientists had to get together to coauthor what amounts of a consensus paper against the bullshit claims in plant "neurobiology".

One of the authors posted it here: http://blumwald.ucdavis.edu/papers/Alpi%202007.pdf
Plant neurobiology: no brain, no gain?

The past three years have witnessed the birth and propagation of a provocative idea in the plant sciences. Its proponents have suggested that higher plants have nerves, synapses, the equivalent of a brain localized somewhere in the roots, and an intelligence. The idea has attracted a number of adherents, to the extent that meetings have now been held in different host countries to address the topic, and an international society devoted to ‘plant neurobiology’ has been founded. We are concerned with the rationale behind this concept. We maintain that plant neurobiology does not add to our understanding of plant physiology, plant cell biology or signaling.
We begin by stating simply that there is no evidence for structures such as neurons, synapses or a brain in plants. The fact that the term ‘neuron’ is derived from a Greek word describing a ‘vegetable fiber’ is not a compelling argument to reclaim this term for plant biology. Let us consider the erroneous arguments that have been put forward to support the concept of plant ‘neurons’. By this logic, cells that contribute to auxin transport are equated to chains of neurons, and it is argued that auxin transport occurs via a concerted vesicle-based trafficking mechanism of ‘neurotransmitter-like cell–cell transport’ [1,2]. There are two immediate difficulties with this reasoning. [...]

The article goes into some detail.

ModVegan wrote: Self-preservation is a natural instinct I don't expect any living thing (plants, animals, etc) to rise above.

Appeal to nature fallacy?
Plants are nothing but their programming; they have no intelligence or mind to override it.
Animals can override instincts, humans perhaps most of all. People regularly sacrifice themselves for things they believe in. Are you saying that a person who dies to save others has done something immoral, or morally worthless?

ModVegan wrote: To call it a right may be excessive, but it is certainly a reality.

All kinds of things are a reality, rape, murder, anger, hate, etc. That doesn't make them good.
You were using the argument as a moral justification, but what usually just happens is not necessarily moral.

ModVegan wrote: I'm not going to hold a survival instinct against any organism,

What about the instinct to have sex and procreate? Will you hold rape against a homely and unlucky man who had no other shot at procreation? Where do you draw the line if you're permissive of "instinct" to violate morality?

ModVegan wrote:But acknowledging self-preservation as an instinct is a far cry from saying we're required to keep breeding cows to preserve their species for them.

If your argument is that we're excused by instinct, rather than by right, then cows are off the hook, but you just opened a can of worms for people to justify actions as instinct.

ModVegan wrote: Plant Neurobiologists like Stefano Mancuso are serious scientists.

No, they're dishonest press whores at best, clamoring for funding and book sales at the expense of the science, and maybe even quacks if they're drinking their own kool-aid.
Notice how he has a book he's selling? Yeah...
The arguments of this crowd amount to dishonest pseudoscience of Intelligent Design advocates, with "theories" like irreducible complexity. It's another literal appeal to ignorance. They think it's too complicated to be explained away by traditional mechanisms, like the ID people think life is too complex to be reduced to evolutionary steps; no evidence for this, it's just an assertion. Then they cobble together a bunch of pseudoscience and weak speculation (already debunked in that article I linked) to justify themselves.
If you do not know the explanation for a particular behavior yet, that only means you don't know the explanation for that behavior, not that there's a secret brain (or a god, when you don't know how something evolved) controlling it all.

If we had even an iota of evidence for any of this, and it wasn't based on some loony unfalsifiable ad hoc hypothesis, then he might be a real scientist working in real theory. As it stands, he's a quack.

ModVegan wrote: They aren't asking anyone to become fruitarians, they are simply interested in understanding plants better and answering questions like, "what's the best way to plant trees?"

No, they're simply interested in selling books, getting interviews, and funding in general. Plant science is hard to get money in unless you're a media whore willing to manipulate the yellow press. Follow the green, and I don't mean plants. They have a substantial motivation to lie, and they're not regarded well by their peers for doing it.

ModVegan wrote:I would venture to say that 99/100 times, this argument is not brought up with any sincerity, but I have no problem discussing it with non-vegans if they are asking genuine questions.

If you want to try that line about eating animals killing more plants and it works, that's fine temporarily.
BUT you do realize that these people consider plants to be "upside down" animals, and that the roots are the actual organism's brain, right? The thing I said about grass fed cows is going to be VERY hard for you to address once you've given into this pseudoscience.
Vegans need to be willing and able to appeal to science to overcome nonsense like this, because if you let the argument drift from reality and hand the till over to your opponent you will always lose. They will steer the course into something you will have no logical argument against, and you'll be stuck on that ride.

ModVegan wrote:Plants clearly have some experience of the world,

No, they don't. It's this kind of assertion that's a problem. You're feeding this stuff. Why?
I don't understand how smart people buy into any of this. Is one TED talk really that convincing?
What did you see or read that has you sold on plant sentience?

ModVegan wrote:though the absence of a central nervous system means it would be on a level completely unintelligible to us (at least at this point). I fail to see the value in belittling that.

That's like saying pocket watches, or crystals, or anything else is intelligent, but since they don't have brains it's just beyond our understanding. It's meaningless.
I fail to see the value in encouraging that kind of anti-science (and anti-logic) thinking. It's harmful to accept the claim that something is beyond human comprehension and therefore (maybe/probably/etc.) it's true; it's harmful to promote and accept that kind of rationalization, and doing so commits you to accepting the same kind of reasoning in other areas as well, basically setting you at odds with science.

You can believe whatever you want, and if you don't feel like you understand the relevant subjects well enough to personally conclude that plant sentience is absurd that's fine and perfectly honest of your, but please don't make supportive assertions for this pseudoscience or suggest that people who find plant sentience (or plant "neurobiology") absurd are being closed minded or ignorant about it. There's no reason to lend more credibility and positive attention to this nonsense.