The case against plant consciousness
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We still do not properly understand it, thus we cannot define it. While I try to stray from vague or ambiguous interpretations, I do think it's significant to point that out.
Let's look at the generic definition: * consciousness - "the state of being awake and aware of one's surroundings." * awareness - "knowledge or perception of a situation or fact."
While a plants' consciousness may not be COMPLEX, it does not mean the absence of conscious. There are things such as cellular intelligence which we know is exhibited in even the smallest of prokaryotes and eukaryotes cells.
At the most abstract interpretation I think consciousness can be defined as a closed system that contain both input and output, in which information is gathered and alters some component of the system itself.
There was a really interesting article the other day on here about how plants were more adaptive to radiation (specifically in Chernobyl) compared to the regions animal counterparts.
To this definition, I think plants exercise consciousness. When we look at life we have to analyze on both the fundamental and complex aspects.
Just my 2 cents.
Following that line of reasoning, you could say that even the smallest particle/bit of energy has some level of consciousness.
Then you could also say that Earth (and any planet or star), is also conscious, and at a way higher level than we (humans) are.
Do you know of this concept has been incorporated into physics somehow? Are there any models in physics that consider panpsychism as fundamental? (i.e. That consider consciousness as a basic property of matter/energy, just like the 3 special dimensions or time)
What's the point of the word "conscious" if it's just a synonym of the word "complex"? If it doesn't add anything, it's not worth having the word.
However, this happens very frequently in humans, we have multiple different languages and even multiple synonyms for a lot of (most?) words in every one of those languages.
At the same time, would correlation of two things make one of them worthless to have/know/understand?
If you're saying they're synonymous, then it doesn't make sense to ask whether you can have one without the other.
So ask yourself, could you imagine something being complex but not conscious, or conscious but not complex? If so, then they're not synonymous and you have something interesting to talk about.
We us as humans on the other hand, want to compare our consciousness to the one of animals/plants/etc.
Trying to bridge the two things, you could say that everything has consciousness, but that there's a "level" of it, which to make it simple, you could attribute to (or be roughly correlated to) complexity/size.
In a way, it's exactly how gravity is defined.
This is very similar to the definition I was given for "robot" in an embedded systems course.
A popular definition (in my experience) is the existence of a central nervous system, but we don’t really know whether or not that’s responsible for consciousness. I wonder if we’ll ever know for sure.
This seems like a reductio ad absurdum definition of consciousness, to echo rotrux's "By this definition my air conditioning system is conscious" comment.
Consciousness may be hard to define, but it certainly is something that at least appears "special", and I think it's a big mistake to not include at least some level of self-awareness in the definition.
For example, is nature (evolution) conscious?
I mean this in the most literal sense, the system which created your definition of "consciousness", is that system itself consciousness?
The material that makes up our neurons once came from a non self-aware system. (basic minerals, etc.)
These are the most boring sorts of arguments. You want to talk about only systems that have self awareness? Fine, you go do that on this side of the room. You want to talk about systems that don't necessarily have self awareness? Okay, do that on the other side of the room.
If you can't decide on common definitions for words, you can't play together.
You seem to be saying that there's a "special" thing, and that thing must include self awareness by your reckoning, and you call that thing "consciousness". Instead of arguing about whose definition of the word "consciousness" is better, just define that thing rigorously, call it anything you want, and then we can talk about it.
In that line, what do you define as a "closed system"? Technically, nothing exists that doesn't somehow interact with its surroundings. Including humans (we breath, eat, absorb/exchange heat from air/sun, etc). Also black holes (Hawking radiation).
For example, a car and a truck are both vehicles, but a vehicle is neither a car or a truck.
The truck or car are the subject/closed system.
When I say an entity is conscious, I mean to say it not only has the ability to react to stimuli, but it can also abstractly choose how to react. It can rewire its own reactions, not just in a Pavlovian sense, but it can also develop internal thought frameworks and route its reactions through the frameworks it prefers.
The only mechanism plants have for improving the way they react to their environment is biological evolution. You could call that mechanism a type of consciousness, but in doing so you would have to treat the species as the conscious entity, not the individual plant; individual plants are like passing thoughts.
Thus I don't think individual plants are conscious unless they have some way to improve their reaction to their environment outside of biological evolution.
So the question shouldn't be whether we can adapt in ways that plants can't but rather what degree of adaptability feels sufficiently thoughtful to our meat computers.
If by "free will", you do mean what I think you mean, it would be very surprising we have it. It would basically imply dualism, which I have dismissed a long time ago.
Of course our thoughts are entirely automatic. They're physical processes like any other. It would still be nice to understand their structure. I for one would be thrilled to learn how choices actually happen.
Simple: it goes both ways. Then decoherence happens, the universe splits in half, and we experience being in either one of those halves. What we observe is but a glimpse of what actually happen. We don't have access to the other side (split universes don't communicate with each other, contrary to what much sci-fi material describes).
That may sound weird, but the alternative (that half the amplitude is "not real", or that it "collapses" (in a way that is non-local, that is, exceeds the speed of light), is even weirder.
Or you could just refuse to answer the question, and stick to "this equations mean I should observe this with those statistics".
Things that don't move very fast are at an advantage where energy efficiency is important. The general trend is that low-energy things modify their environment chemically and high-energy things modify their environment mechanically. Compare the diversity of human-discovered secondary metabolites from plants/fungi (low power), insects/reptiles/amphibians (medium power), mammals/birds (high power)
https://www.mpg.de/15791/Plants_and_environment
https://en.wikipedia.org/wiki/Plant_communication
https://pdfs.semanticscholar.org/6b23/df2807a0fb8e77c4922377...
I can imagine an experiment where some plants are placed in an environment where the communication chemical they secrete interacts with a gas in the air, slowly poisoning the plants. Would the plants adapt by changing their own behavior, or would some later generation survive due to a mutation? If they changed their own behavior, that might point toward a kind of individual consciousness.
More importantly as we understand more about the brain we may eventually understand how everything works. Any definition that would then exclude humans as conscious becomes irrelevant.
Which has an interesting parallel with many plant's ability to rotate the face of their leaves towards the current position of the sun.
From a philosophical standpoint, and considering the spirit rather than the details: Is this hypothetical experiment just giving plants a challenge at them which they're too dumb or helpless to solve?
It seems there are plenty of analogous challenges which humans alone or in groups are unequipped to deal with.
Is any "challenge" humans respond to not a homeostatic correction, like if everything were perfectly perfect for a person would they do anything different at all? Considering also the homeostases we're built to maintain "just because", like novelty vs boredom.
If a thing "decided" to change its reproductive rate, or selected different sexual partners based on environmental conditions, is this necessarily a phenomenon unconnected to individual agency? Humans do this too.
Developmental neuroscience strongly supports the claim that physical brain architecture requires environmental stimuli, and psychology strongly supports the importance of "nurture" contributing to a person's "self". Do these stimulus responses have no bearing on consciousness?
If your conscious experience suddenly became transferred to a tree, and a lumberjack came to cut you down, how could you convince them you're conscious using the behaviors available to you?
Consider a conscious alien unfamiliar with human society, or a Stone age tribesperson who somehow doesn't embody human cognitive biases like assuming consciousness of things that look like them. If they observe a financial services office for a few hours, do they think the workers are modifying the environment in an individually considered manner?
If plants and humans were both considered by definition to be conscious, would life change?
These are just reactions with a memory component. This would include any computers, and so is too broad. I think consciousness will end up being a specific type of information process, with certain properties including those you describe, but it must have more properties and so be more specific than what you outline.
Saying this because the definition seems to beer toward “free will”.
Ah, that's a biiig claim. Which may be true nonetheless. Can you be more precise in this context about 'intelligence' as distinct from action-reaction?
BTW there is a claim that plants can be conditioned a la pavlov. I'll try to dig out the ref (recently in new scientist). Amazing if verified.
> about how plants were more adaptive to radiation
Adapted in this context means adaptations so as to 'not die' I suspect. Please correct me if needed.
Life forms that don't move don't need brains. Sophisticated decision-making isn't a challenge that a plant has to meet. I think this is a strong point against the idea of plants being conscious.
https://www.ted.com/talks/daniel_wolpert_the_real_reason_for...
Imagine waking up from deep sleep. In the first few seconds, there is virtually no intelligence present other than basic autonomous body survival intelligence, which is also present during deep sleep. So what has changed? What is the difference between being in deep sleep and being in the state of unintelligent awareness a second after waking from deep sleep? There is not something that it is like to be in deep sleep. There is something that it is like to be just awakened from deep sleep.
There is a lot of confusion in most conversations between consciousness, intelligence, and self-awareness. The three are different concepts and the relationships between them are poorly understod.
I can imagine a human-level intelligence that lacks consciousness (this is sort of what is meant by the term 'p-zombie'). I can imagine a being that almost or completely lacks intelligence (in the sense of problem-solving ability, pattern recognition, etc.), yet is conscious.
Humanity currently has a lot of knowledge about how various material phenomena (drugs, being hit in the head with a brick, etc.) affect consciousness, but as far as I know humanity currently has zero knowledge about the mechanisms by which material phenomena affect consciousness. Consciousness in its essence is not understood at all and may be fundamentally beyond the reach of science.
There is no reason to assume that it is in principle possible to objectively evaluate whether some entity is conscious.
Maybe, but probably not!
> I can imagine a human-level intelligence that lacks consciousness (this is sort of what is meant by the term 'p-zombie'). I can imagine a being that almost or completely lacks intelligence (in the sense of problem-solving ability, pattern recognition, etc.), yet is conscious.
I can imagine living forever, but it's actually impossible. The p-zombie argument depends upon a rhetorical trick that exposes our ignorance, much like Zeno's paradox.
> There is no reason to assume that it is in principle possible to objectively evaluate whether some entity is conscious.
Whatever argument you might use to to justify this, would also suggest that it is not possible in principle to objectively evaluate whether something is healthy, or alive or feels pain. And yet we seem quite adept at this.
Why closed? Who says it is closed? I claim it is open, and, spans the entirety of physical reality, fully entangled.
> ... that contain both input and output, in which information is gathered and alters some component of the system itself.
That sounds like a model for computation not consciousness. A JIT compiler would qualify.
Edit: just saw a small snippet on plants down the page but if anything, i think kin selection in and of itself is supporting of consciousness. I have a hard time imaging non-conscious subjects exhibiting kin selection.
Why would you think that? Evolution operates on a population via shaping the distribution of traits via selection. The selection is being done by the environment, not the population, and requires no conscious entity.
It's evolutionarily plausible and explains a massive range of traits and behaviors up through full altruism. See eg. "gay uncle" hypothesis: https://en.wikipedia.org/wiki/Biology_and_sexual_orientation...
I would describe kin selection as a phenomena that is caused by natural selection because natural selection is a phenomena describing propagation of genes and not propagation of individuals. This is a subtle point and often not taught unless taking specific relevant coursework (I learned about it in an animal behavior class).
I am likely using slightly incorrect phrasing and evolutionary science experts may phrase things differently, though I am confident in the essence of this argument.
This is simply a false statement. Kin selection isn't distinct from natural selection. Kin selection is the idea that a trait could be harmful to an organism but if it confers sufficient benefit to close relatives (who are likely to have the same gene), the trait can be favored. It is one of the core ideas of "the selfish gene" view -- that from an organisms vantage point such a trait should go extinct, but viewed from the gene's vantage point, it is a desirable trait.
i.e., the former requires intent, whereas the latter simply evolutionary pressure (since the trees with the response would fare better, thus reproduce more successfully).
If a single tree under duress is using its resources and energy to signal to other trees that have no way of directly helping the tree in question, what evolutionary advantage is being provided to the tree releasing the pheromones?
Not sure I am able to expand on this but it seems that the trees may have an awareness of your last line: "since the trees with the response would fare better, thus reproduce more successfully", and that awareness may be a form of consciousness different than our own.
<https://asknature.org/strategy/leaves-signal-presence-of-pre...
> If a single tree under duress is using its resources and energy to signal to other trees that have no way of directly helping the tree in question, what evolutionary advantage is being provided to the tree releasing the pheromones?
Its genetic legacy is being enhanced, if the trees it's protecting are related, which likely they are (very elegant phrasing though! upvoted just for that)
> thus reproduce more successfully", and that awareness may be a form of consciousness different than our own
Hmm. Be careful here. I need to sit down and read and understand this so please recognise I'm dumping this on you, but
"Michie’s design, called MENACE, was a large pile of matchboxes that contained a number of beads and learned to play tic-tac-toe."
...
"MENACE could never win against the perfect algorithm, but ended up drawing every time after about 90 games, making it equally as perfect"
<https://opendatascience.com/menace-donald-michie-tic-tac-toe...
I dunno. Where do you draw the line? HTH anyway.
the response requires no consciousness, only a mechanical operation
> what evolutionary advantage is being provided to the tree releasing the pheromones?
natural selection works in perpetuity; "this" tree benefited from the action/reaction it has, thanks to its parents having the same reaction/action. The reified response then promulgates because it helps the bearers survive, and becomes self-reinforcing.
[1] https://fas.org/irp/program/collect/air1995.pdf
[2] https://med.virginia.edu/perceptual-studies/wp-content/uploa...
[3] https://med.virginia.edu/perceptual-studies/publications/aca...
[1] https://med.virginia.edu/perceptual-studies/wp-content/uploa...
I submit that what we think of as "consciousness", the awareness of being, is impossible within a model based purely on objectively measurable criteria.
https://www.imdb.com/title/tt0117040/
https://en.wikipedia.org/wiki/Microcosmos_(film)
Some of the scenes in time-lapse ("fast motion"), you can see how plants reach out their vines and leaves, moving and feeling the world around them. So, at least they seem to have a level of "awareness", by some definition of the term.
Anecdotally, I've had countless experiences of what might be called "consciousness" in all living beings - but then again, it depends what one means by that word.
Edit: I mean, is a maze-solving slime mold conscious? And what makes human consciousness so uniquely different from slime mold's?
> how plants reach out their vines and leaves, moving and feeling the world around them
I could argue cold water dropped into a very hot pan 'spreads out' to 'feel' its environment, 'withdrawing' from the metal where it can.
Good point about a water droplet's behavior, how it seems to be "alive" in some aspects - all due to physical/chemical reations. I think it's related to the question of what "alive" means, and how it's different from inert, non-living material.
With slime mold, much of its behavior is just like water - spreading, dripping, with surface tension, etc. - but there's definitely a difference (perhaps only subjectively), that an observer would say it "feels its way" toward a food source. I suppose the fact that we ascribe "feeling" to it, means we consider it alive, aware, and perhaps conscious.
Seems it goes further. "People are irrational. Example: You wouldn’t buy a new dress, or suit, that costs $100 (‘that’s far too much to spend!’) but you would buy one that was $300, but is now ‘reduced’ to $150 (‘but just look at how far down it’s come!’) Sound familiar? You’re not alone, it’s fairly well-known that humans are irrational (at least by those in advertising- some products in supermarkets are never meant to be bought- they’re just there to get you to buy other products more), but are other animals just as irrational?"
Turns out slime moulds fall for it too. Full article https://blogs.scientificamerican.com/not-bad-science/think-y... That really complicates thins.
All that said, I am really uncomfortable talking about consciousness in these contexts at all, for obvious reasons. When we can identify and quantify, I'll talk. See my point elsewhere about matchboxes learning.
Edit: fixed link
> slime moulds make decisions through comparison to the other available options, rather than having an intrinsic value for things
That sense of subjectivity and "thought" process to make decisions, sure sounds like consciousness to me - but then again, a stream flowing down a mountain also "makes decisions", and I'm not sure if there's a quantifiable difference.
I just read the article you linked elsewhere: How 300 Matchboxes Learned to Play Tic-Tac-Toe [0]. When we call a completely mechanical process "learning", it seems to imply some kind of subjectivity and "thinking".
It's hard for me to pinpoint, what is the difference between a human and a machine learning? The difference seems merely the level of complexity.
Discussion about consciousness usually breaks down, I think, because the root of this concept is in our belief systems and philosophical view of life. At one end of the spectrum, all of existence is "conscious" in varying degrees; at the other end, nothing is really "conscious", it can all be explained as mechanical processes. The latter used to be a "heretical" worldview, to deny the "spirit" pervading all creation. These days, I'd say the former view is the odd one out, being unscientific (without experimental evidence) and based on an iffy definition of consciousness.
https://opendatascience.com/menace-donald-michie-tic-tac-toe...
---
Edit: Here's a quote I just came across:
> Freeman Dyson argued that "mind, as manifested by the capacity to make choices, is to some extent inherent in every electron."
..And a comment elsewhere mentioned, "consciousness as an emergent property of physical systems". That seems to be getting closer to a reasonable definition/explanation.
If you like slime moulds then, just in case you haven't met Dictyostelium discoideum, check out that on youtube. It goes from a collection of single-cells to a 'slug', a small multi-cellular organism which goes for a wander. Quite mind-blowing when I first met this behaviour.
All I can say is consciousness is a bugger. Everyone seems to have some idea of what it is except me, and I'm not going to claim that I am. I just don't know.
Anyway, a pleasant and constructive discussion, thanks!
I'm going to be following along here for quite some time I suspect...
This is a hard question and the Feinberg-Mallatt definition of consciousness seems circular.
An artificial or alien life form might possess consciousness without having traversed the same evolutionary trajectory as animals, and will probably not possess animal neurons. Even a sufficently diverged animal might use novel strategies for organizing neurons (or alternatives to neurons?) to sense, move, focus attention, and remember.
Because neuroscience is bigger business than philosophy.
There is no such thing as consciousness, i.e. a mechanism that defines consiousness.
There is only a simulation process inside organisms that tries to mimic reality in order to predict the outcome of the current situation and subsequently produce a 'get away'-oriented or 'stay'-oriented response.
This simulation process' complexity is relative to the complexity of the organism.
The more complex the simulation is, the clearer the definition of objects in it is.
The clearer the definition of objects is, the clearer the definition of self is.
The clearer the definition of self is the higher the degree of 'consciousness' is.
I.e. consciousness can be defined as the ability of something to perceive itself.
With that definition, it is clear that that ability of self-perception changes from organism to organism.
Thus plants have a low ability to perceive themselves, and humans have the highest.
If we are searching for the mechanism of consciousness, we will never find it, because it doesn't exist: consciousness is an emergent phenomenon that arises from the operations of an organism.
The relationship betwen brain structure and consciousness is so poorly understood that this statement is basically idiotic. We know various ways to affect consciousness in humans. For example, using blunt force or drugs. However, we have no understanding at all of any mechanisms by which matter gives rise to consciousness and we cannot even be sure that matter does give rise to consciousness. And we have no way to evaluate the relationship between matter and consciousness in non-human entities like plants that do not communicate to us in any understandable (to us) way about their consciousness or lack of it.
It often amazes me how many people are highly advanced in their own technical fields but fail to grasp the hard problem of consciousness - something that can be understood by a bright kid.
in speculation perhaps the concept of consciousness as an emergent property of physical systems should be explored. if consciousness is dependent on persistence of a quantum mechanism it is possible for consciousness to exist as a result of any sufficiently spanning rule parsing interactions; And i'll just leave this right here;
There's still the level of consciousness and intelligence to look at.
I eat everything but octopus/calamari. I think they are too intelligent to eat. I've seen smart cows, and if I didn't grow up eating beef and it wasn't such a great source a protein, I would cut it out too and just eat chicken. For me it's where do I draw the line of intelligence of what I want to eat. The less likely the animal can comprehend what's going on, the easier I feel about it.
I can't eat Octopus, Pigs, Dogs, or any type of Ape because they are too aware of the process.
Oddly I don't have the same aversion to Dolphins or Whales. They may have a comparable amount of intelligence to animals that I wouldn't eat, and a dolphin is even cuter than an octopus, but for some reason I don't have a problem identifying them as food. Sort of like Sheep and Goats, they are cute, but also clearly labeled as food in my head.
It's impossible to live and thrive without being detrimental to other organisms - for me, the idea is to accept the inevitable cycle of struggle and violence, while minimizing the _exploitative treatment_ of other beings [plant or animal -- easier said than done with regard to plants -- one easy step is to include as much fruit and perennial leaf matter in the diet as practical [i.e., the plant is treated more like something to be nurtured rather than merely 'grown and discarded']
You could say the same about breeding animals for meat or even people for slavery - in fact that seems to be not to many steps down that route. I don't think either are acceptable though, so we're back to deciding where to draw that suffering line.
Or economically valuable for organ extraction.
http://content.time.com/time/magazine/article/0,9171,138483,...
> [Labs] at the University of Texas and at the University of Bath ... created headless mice [and] headless tadpoles.
> "It would almost certainly be possible to produce human bodies without a forebrain," Princeton biologist Lee Silver told the London Sunday Times. "These human bodies without any semblance of consciousness would not be considered persons, and thus it would be perfectly legal to keep them 'alive' as a future source of organs."
Something like: See, even plants are conscious, there is no point so let's just continue eating steaks and pork chops every day.
It is hard to imagine that anything with eyes doesn't have this, and yet functioning eyes are clearly not a requirement. The only requirement at all one would assume is integrated information processing - but even that is not necessarily a given.
It may be that consciousness is a net positive to us in that it lets us adapt to conditions more quickly. Our genes may last longer than plant genes as a result. But it also burdens us with destructive tendencies that threaten our survival. The jury is out.
No it doesn't, but that's not what's at debate. The fact anyone needed to be told plants aren't conscious is kind of crazy.
There's an insinuation that level-of-consciousness is the measure by which we should judge the importance of organisms. This is an anthropocentric view of life, and a shallow one at that.