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Comment by taneq | Hacker News Reader

> “Plants are not just robotic, stimulus-response devices,” said Frantisek Baluska

I don't see how this follows from the finding that sedatives can prevent plants from responding to stimuli. It just means that there's a shared mechanism behind plants' responses and animals' responses, which wouldn't be overly surprising.

Of course, that doesn't mean that plants don't have a lot more going on than we usually realise, just because it happens at timescales so much longer than ours. There's all sorts of cool stuff happening in rainforests with cooperation/competition between plants.

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I'd add that "robotic" is, in most uses of the term, extremely vague. In those uses, it doesn't have a clear meaning, it's just a term for referring to things that appear like how present-day automated machinery appears to us.

It's like people who think "computer" means something that appears like the kinds of silicon-based computers we engineer at present, rather than understanding it in terms of the rigorous notion of computation, as something that can perform computation (which can be performed in such widely varying ways, in so many different media)

Moreover, I can have say, my limbs anesthetized, yet remain conscious. I can also be unconscious (sleeping) yet respond to stimuli.

The author of the article seems to assume that loss of responsiveness implies a consciousness which is lost, which is frankly a bizarrely incorrect inference.

It reads to me as: Here is a list of examples of things that plants do that would imply some kind of decision making process. When we anesthetize them they lose those abilities, is that something that tells us they have consciousness.

Secondarily, one can make the argument that due to the fact that you have a nervous system in your arm and your brain loses the signals from that system, in some way you have lost part of your consciousness when you are anesthetized. Since at it's core consciousness is just an awareness of what is happening to you.

Thirdly, whose to say if plants are conscious that their roots don't function in some way as their brain.

My understanding of the traditional definition of consciousness is explicitly not the simple stimulus/response you imply it is, but rather, meta-awareness or control over the stimulus/response system.

That is, I am conscious of my arm if and only if I am aware of the stimulus/response process taking place (or not, as it were). Whereas, there are plenty of processes in the body of which one is not typically conscious (e.g. heartbeat, digestion, anything occuring during sleep or coma).

To claim that you suffer partial loss of consciousness when your arm is anesthetized implies that when asleep, you are not fully unconscious, because your arm still responds to stimuli. This is contrary to almost every definition of consciousness I've heard, and sounds more like a definition of responsiveness.

The model of plants wherein all stimuli/response processes are unconscious I claim is not invalidated by the experiment in the article.

Yet this is the same type of work people are using to argue that that crabs/fish can feel/experience pain. Proving or disproving consciousness is basically impossible.

E.g. I feel like a lot of people aren't conscious :) Prove me right or wrong?

I know where I came from — but where did all you zombies come from?

So would you allow me to chop up someone you have decided is unconscious? If the answer is no, why?

I shared the impossibility of making such a decision with any degree of certainty.

But we have to eat. I'm no longer sure what's more ethical: eating something dead meat or vegetables that are still alive.

The best explanation demystifying consciousness I've found comes from a claim it's a social phenomena that only arose around 3000 years ago:

https://en.wikipedia.org/wiki/Bicameralism_(psychology)

These days most people are conscious because you need it to function in society; there is a good deal of evidence in the book.

"It is one of those books that is either complete rubbish or a work of consummate genius, nothing in between! Probably the former, but I'm hedging my bets." - Richard Dawkins

I wonder how you'd spot a Bicameral person in modern society.

> Yet this is the same type of work people are using to argue that that crabs/fish can feel/experience pain.

Not really: a fundamental requirement in the assessment of pain reception in animals is the presence and stimulation of nociceptors (pain receptors). Plants don’t have any nerves, so they fundamentally lack pain reception. It’s entirely possible that they have developed an alternative system to experience pain (e.g. via analogous action potential signalling) but at this point our conventional model of pain reception completely breaks down.

We could connect a nociceptor to a computer. Does the computer now experience pain?

Just because the mechanism exists for sedation or pain does not imply the experience of consciousness or pain.

I’m not arguing that. I’m arguing that a nociceptor is necessary but not sufficient to argue for pain experience. And plants don’t even fulfil this basic, necessary criterion. So the “type of work” shown in the article isn’t the same kind of evidence conventionally used to argue for pain experience.

The correct statement is "Plants are less [more like robotic, stimulus-response devices than people are] than previously assumed."

The hard question is, how large is the spectrum between Robotic and Conscious and at which point it is reasonable to suspect Consciousness?

Spectrum? Between?

The hard thing is to be less reliant your assumptions and start figuring out what to start measuring.

edit: s/ditch/be less reliant on/

edit2: even that's not quite right; the derivative I'm reaching for is first testing the validity of your assumptions

For all I care humans are "just robotic, stimulus-response devices".

I mean I also have a physicalist materialist view of the world but that's exaggeratedly simple

> that's exaggeratedly simple

it's simple, but I don't think that it's exaggerated. If anything I think it just speaks to the hidden power and complexity that can arise from following simple rule-sets.

Although not typically used to describe such (internal) behavior, the text-book definition of 'stimulus' is just "a thing or event that evokes a specific functional reaction in an organ or tissue." -- If one were to consider that definition, 'stimulus' would also include everything your brain does; along with introspection, prediction, and everything we include as 'consciousness', and not just external forces that evoke an internal response (like sound,smell, light, touch, taste, etc.).

If you take that stance you also say there is no such thing as free will, since all your actions are some kind of response from the environment.

Not saying that that means you're wrong.

You can still experience "free will" without invalidating the materialist point of view: https://en.wikipedia.org/wiki/Self_model

> You can still experience "free will"

if you have to put quotes around it, is it really free will?

I had a look at that link and I don't see anything related to free will there... what's the link you're suggesting?

The quotes are there to indicate that the free will is there but only as a convenient abstraction.

"The idea of the self over time [...] is the property of phenomenal selfhood that plays the most important role in creating the fictional self and the first person perspective. Metzinger defines the first person perspective as the “existence of single coherent and temporally stable model of reality which is representationally centered around or on a single coherent and temporally stable phenomenal subject”."

Free will in this sense is used to model reality in the form of subjective experience, part of which includes ownership of self. In other words we experience free will as a property of our model of reality, but it does not exist outside this abstraction. Objectively we are causally determined, subjectively we experience free will as part of the modeling process by the brain to create predictions about how it should respond to external stimuli.

Self is an abstraction inside a simulation, it does not map onto reality directly. But since our subjective reality is the simulation, we will always experience ourselves as having free will barring a brain disorder, such as the ones mentioned in the wiki link: "Disorders of the self model are implicated in several disorders including schizophrenia, autism, and depersonalization."

I don't think there is actual free will, and I think the appearances of it is just how our minds present things to us -- that is, I basically agree with the description you give.

But I object to statements like:

> the free will is there but only as a convenient abstraction.

Here's an analogy to illustrate my objection. It's inaccurate to say that the person Santa Claus literally exists but only as a mental concept.

The accurate way to put it is that the Santa Claus person doesn't literally exist but we have mental concepts describing such a person.

Free will doesn't exist but we have a mental concept of such a thing.

That's the honest way to put it.

I think that's a fair point. I usually phrase it that way to avoid coming off too strong to people whose beliefs are unknown to me.

So to sum up, we agree that the concept of free will exists and is experienced, but it is just a mechanism that the brain uses to navigate and make decisions about a dynamic environment and not free will in the classical sense of having control over the decisions we make.

Honestly, after writing that out, I agree even more strongly with you! I think we should relegate the term "free will" to the classic definition and adopt Metzinger's vocabulary for the new metaphysical concepts. Then it's very simple, there is no free will, but there is a Phenomenal Self Model that the brain relies on which can be conflated with classical free will.

I will endeavor to be more clear in the future. Thanks!

The hard part is coming out with an interesting and discussable definition of free will that doesn't smell like the mind-brain duality, which is just a term for spirit.

> Not saying that that means you're wrong.

Your statement presumes that the typical conception of "free will" does indeed exist and that this is a universally held position. As a counterpoint, determinism has many backers.

A typical (grossly simplified) physicalist response to your claim is that the illusion of "choice" is really the result of complex processes playing out.

>there is no such thing as free will, since all your actions are some kind of response from the environment

And why couldn't that be free will? https://en.wikipedia.org/wiki/Compatibilism

I think an important distinction is whether the response to stimulus is hardcoded or not, and the degree to which it's not. Saying simply 'stimulus-response' makes it sound like a reflex like pulling back your hand when you accidentally touch a hot plate. There's a world of difference between an automaton that always reacts the same way to a given stimulus on one end and on the other end a deeply learning mind that can store memories, create internal models to predict stimuli, maybe even 'rewire' itself to change what effects future stimuli can have. Sure, you could say that the latter just reacts to stimuli over a greater period of time (e.g. experience is just old stimuli still being reacted to) but to do so would be to gloss over the enormous difference in nature and complexity of such systems. And unless you believe in a metaphysical definition of consciousness, then somewhere in that complexity gap is where consciousness arises, so it seems hardly like something to be glossed over.

Suppose it is hardcoded? what difference does that make?

edit: I know about hardware and software, but since we are all wetware, maybe we should think about it as its own class and/or function?

You didn't read the article I guess?

This paragraph provides answer to your objection. Plants learn to modify the response based on experience.

> Under poor soil conditions, the pea seems to be able to assess risk. The sensitive plant can make memories and learn to stop recoiling if you mess with it enough. The Venus fly trap appears to count when insects trigger its trap. And plants can communicate with one another and with caterpillars.

While it's correct, it hides peculiarities of humans' stimulus processing.

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