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Microbial consciousness, plausible?

  1. Feb 2, 2007 #1
    Everyone here knows that science has not figured out how the hell the brain does it, or even if it does it. Some scientists think microbes are conscious, that that they experience something. Here are two quotes from Lynn Margulis:

    Most peoples first reaction at this idea will be something like shock and ridicule. After all, microbes are so different from humans. Humans read books and do math, microbes dont. Thinking that microbes are conscious is to attribute human traits to non-human organisms, and this surely is a serious mistake (also known as anthropomorphism).

    But, there is a flip-side to the coin, because if we say that consciousness is a purely human or human-like phenomenom, then we are projecting human traits to consciousness. This is like projecting human traits to 'life', believing that if something doesnt have 2 legs, 2 arms, etc. then that something isnt alive. Or projecting human traits to 'communication', believing that if something doesnt use english words, then it doesnt communicate.

    Or as Margulis would put it:
    "The idea that only humans are alive, makes me laugh."
    "The idea that only humans communicate, makes me laugh."

    But what about consciousness?

    Here are some more links about margulis her ideas:
    Last edited: Feb 2, 2007
  2. jcsd
  3. Feb 2, 2007 #2
    I am interested in any and all theories regarding consciousness. If microbes are conscious, wouldn't consciousness then reduce into either chemical interactions and the reactions they produce or quantum effects? I have never been able to grasp the concept that phenomonalogical consciousness is the product of organized patterns of neurons or electrons in any capacity.

    Also, we might want to define consciousness. It is not the qualities of thought, memory, communication, etc. that defines our consciousness.

    It is the experience itself!

    Since microbes don't have conventional brains, what purpose is our brain in generating consciousness? Perhaps consciousness is a purely subjective experience, belonging exclusively to the specific architecture and engineering present in the organism, one which we can not transcend to postulate other types of consciousness. For instance, humans share similar conscious experiences because we are physically, essentially identical in our architecture. Whales experience a specific type of consciousness, exclusive to their architecture, etc.

    Another question which I am always interested in, is how a non-sentient universe is able to dynamically evolve towards an engineering of conscious, sentient entities, like ourselves. This would indicate that the universe is encoded for consciousness!

    It is an abstraction but valid none-the-less.
    Last edited: Feb 2, 2007
  4. Feb 2, 2007 #3


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    You've misinterpeted her statements. She's not arguing that microbes have consciousness, but that humans aren't in any way special. In other words, that everything still boils down to chemical reactions and responses to stimuli.
  5. Feb 2, 2007 #4
    That is the impression that I received after reading the paper but I was reserving judgment until the OP explained his position more clearly.
  6. Feb 2, 2007 #5
    Do u have a source to show this?
    I agree that the natural implication of microbial consciousness is that humans arent as special/unique as they think they are.
  7. Feb 2, 2007 #6
    We can model memory, aspects of simple cognition, basic language and communication, problem solving, etc. in Newtonian Neural Networks of Consciousness, however, we are unable to model phenomeonalogical consciousness, or experience.

    For instance, humans experience numbers, symbols, letters, concepts, colors, memories, perceptions, ideas, etc. in a unique and subjective way.

    I am sure you are familiar with Church-Turing machines and algorithms. We can program and model algorithms which ensures the machine will arrive at a specific conclusion, however, the machine does not actually understand the algorithm itself.

    It is this property of consciousness, the actual experience, that is unique to sentient organisms.

    I am still of the impression that consciousness is an emergent property of the physical and chemical architecture of the brain. When one considers water and it's property of wetness, one does not seperate 'wetness' from water. Instead, one speaks of wetness as a property of water.

    This is how I view consciousness, an emergent property of the brain's architecture. I do not see the reason to seperate consciousness and the brain into two seperate substances as they are appear as both aspects of the same thing.
    Last edited: Feb 2, 2007
  8. Feb 2, 2007 #7
    Thats a good question. If we can deduce the function of subjective experiences in organisms, we could use this logically to determine if it is required in microbes.

    What do u mean with this?
  9. Feb 2, 2007 #8
    Well, we can't deduce anything because the premises do not necessarily contain the conclusion. However, we can induce a causal relationship from observation.

    We experience consciousness and assume that our experience can and should be applied universally, across macroscopic wholes. For instance, consider the ant and the human, permitting anthropomorphism for demonstrative purposes:

    The ants demonstrate social order, communication, hierarchy of social status, war, slavery (they enslave aphids and give them different roles such as cattle, workers), etc.

    The humans demonstrate similar characteristics (historically, we fought in the same fashion the ants fight, lines of soldiers marching towards battle) and various other characteristics.

    Naturally, we assume our conscious experience should be applied to the ants and since we can assume they have no knowledge of mathematics or physics, that they are not conscious or are chemical machines.

    However, what I am postulating is that if consciousness is a purely physical phenomena, one that emerges out of the physical and chemical architecture of the organism's brain, then perhaps each conscious experience is causally related to that architecture. We assume the qualities of our experience constitutes consciousness when each organism could experience an entirely different mode of consciousness, which because of our subjectivity, we can not transcend to explore.

    I have always wondered if we do not have the perceptual skills or awareness to identify qualities of consciousness in other organisms because consciousness is so unique to the physical architecture.

    While humans all experience reality differently, we all have a similar experience because our brains and bodies are relatively the same. Whales are the same, ants are the same, etc. Since we share similarities, we share similar conscious experiences but it is a non sequitur to assume all qualities are the same because of this.

    It's purely conjectural, nothing unique and very obvious. I am just rambling. If I were asked to formulate a logically rigorous argument in support of this, I might not be as inclined to provide this answer. :P

    I am bored at work and trying to type in a rush so I hope that is coherent, if not i'll rephrase it later.
    Last edited: Feb 2, 2007
  10. Feb 3, 2007 #9
    U mention that it emerges out of brains, so that would rule out microbes, but i wonder what is unique about brains. Brains have neural networks and microbes have metabolic networks.

    There is a part of our brain called the reptillian complex:

    So ur idea is not strange and makes sense, there is a physical structure that resembles that of other organisms, and this goes down not just to parts of our brains, but right to the scale of our cells. So as far as reductive materialism is concerned, i am puzzled why it would (paradoxically) reject reduction beyond the brain.
    Last edited: Feb 3, 2007
  11. Feb 3, 2007 #10


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    Well, if they're conscious, then I guess I should feel worse about incinerating them at the end of a wire loop or tossing them into a phenolic solution at the end of a plastic loop.
  12. Feb 3, 2007 #11


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    Hi Pit, thanks for all the references. Interesting post.

    From reading the references it sounds to me like Lynn Margulis is using the term "consciousness" to mean phenomenal consciousness as opposed to simple behaviourism. Would you agree?

    Computationalism generally suggests that p-consciousness is an emergent property of the entire brain, which conflicts with any suggestion that microbes have some form of p-consciousness. However, there are some that have already proposed that p-consciousness is a property of a single cell (ie: neuron). Steven Sevush wrote an interesting paper about this here:
  13. Feb 3, 2007 #12
    I agree.

    Interesting theory, i will have a look at it. I had some thoughts about microbial mind earlier today like that. I thought perhaps, if each microbe is conscious, then the more they communicate with eachother by sending signals back and forth, then eventually they become so interdependent that not only do their physical structures 'merge', but also their consciousness(think of a bacterial colony that behaves as a whole). I know Dennett and others have no problem splitting mind over different parts of the brain, and these ideas by splitting them over different neurons or even different microbes go along with this reductionism.

    Talking about computationalism, there are many links about bacterial computation in google.
  14. Feb 3, 2007 #13


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    It's in your source. It's pretty clear from her statements in that article.

    Complexity. Brains also have metabolic functions, but have more layers of complexity beyond that. Note that microbes don't have to communicate with each other, just react to chemical or photic stimuli in their environment.

    What this discussion really is touching upon, but not directly addressing, is the age-old mind-brain dualism debate among philosophers. To biologists (neuroscientists), consciousness is just a manifestation of the complex chemical reactions and neuronal networks within the brain. There are philosophers, however, who instead argue that the "mind" (and consciousness) is distinct from the brain. This is the context of the comments made in the opening post...to a scientist, consciousness is just another set of chemical reactions occurring within the brain. It's only the philosophers who put a different spin on it.
  15. Feb 4, 2007 #14
    Lets just let margulis speak for herself:

    So thats enough about her.

    What is it about that particular complexity that would form consciousness, whereas the also complex functioning of microbes would not?

    The same can be/is said about neurons, that they just react to chemical reactions in the brain. A lot of scientists would love to be able to describe the brain completely in physical terms, but they cant because we all know from experience that there is more to it. There is the question of why an organism would need any subjectivity to be able to function - couldnt physical reactions just do what they seem to be doing without it? The answer to that is most likely, i think u would agree, 'no' (if it were 'yes', it would rob consciousness of any evolutionary use).

    Also here are some links about bacterial communication:

    Since we are still talking about physical structures as the basis of consciousness here, there is no need for dualism to consider microbes being conscious. Margulis, and also Hameroff, think that microtubules may be responsible for the computation that produces consciousness.

    Shapiro is another scientist who thinks bacteria are sentient:

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  16. Feb 4, 2007 #15


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    agree. Isn't it really the philosophers that support computationalism? I'm not aware of any recent philosophers of mind that support any kind of dualism, and generally they support computationalism. Searle, Putnam, Harnad and a few others stand out as those that don't support computationalism, but they don't support any kind of dualistic approach either.

    I was wondering if she supported some kind of quantum approach, but I wonder why microtubules. What other structures in a cell might be usefull?

    Here's a thought experiment. Take a neuron out of a brain and put it into a special petri dish. This dish subjects the neuron to all the same exact stimuli it had in the brain, including synaptic actions, em fields, etc. We might for example take recordings of the interactions while the neuron was in the brain and duplicate a series of actions on the single neuron while it was in the dish. Would such a cell have p-consciousness? Obviously from the perspective of the single cell, it would by definition have no ability to discern whether or not it was inside the brain or in the petri dish.

    Now take all the rest of the neurons in the brain and put them into similar petri dishes. If all these neurons have no way to distinguish whether or not they are inside a brain or inside a petri dish, how can any phenomenon created by those neurons be different? I don't think there is any way. They must create all the same phenomenon, including consciousness.

    In the case of a single bacteria, the signals it gets from the environment are limited to the random noise of the environment. The signals a neuron in a brain or petri dish gets is different, it is highly coordinated input from other neurons. From that thought experiment, I wouldn't think a bacteria would have an experience anything like a neuron would, the experiences would be quite different. But large groups of bacteria signaling each other might also create a coordinated input, albeit nothing nearly as complex as a neuron in a brain.
  17. Feb 4, 2007 #16
    Would this simulation in a dish include phenomenal stimuli?

    Wouldnt u end up with about 100 billion brains, one for each neuron? Im not sure i understand the point of ur thought experiment.

    But lets suppose different types of cells/microbes, also produce different kinds of experiences(like our 5 senses do). If these different types start interacting witheachother in such a way that they form networks/colonies then, like in the brain, the phenomenal aspects would also start influencing eachother, producing new kinds of experiences. Causality between experiences is something that may create something 'different'.

    Yes a single bacteria would have quite a different experience because of the type of information it receives. U might compare it to a person living on a deserted island and one living in an internet cafe.
  18. Feb 4, 2007 #17


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    What is "phenomenal stimuli"? If we assume the only stimuli given to any cell is in the form of light or em fields, molecules interacting at the cell surface, etc… then all these stimuli are essentially classical in nature. I think we should steer clear of 'special signals' that include something above and beyond the interactions science presently looks to explain.

    Let's assume there are no 'special signals' such as "phenomenal stimuli". If every neuron is doing exactly what it was doing prior to being put into a petri dish, there's no way for any of the 100 billion neurons to distinguish between life in a petri dish and life in the brain.

    If there's no difference between the petri dish brain and the connected brain (I'm suggesting there is no difference), then p-consciousness is a property of individual cells.

    I'm not suggesting how a single, unified experience might come about from the interaction of neurons, I'm only suggesting (and agreeing with the OP) that consciousness is a property of single cells. Note that Sevush addresses this issue to a degree in his paper. I'll have to reread his paper again, it's been quite a while since I read it. But he takes up the challange of how numerous individually conscious cells within a person's brain might create the single unified experience.
  19. Feb 4, 2007 #18
    Phenomenal stimuli are experiences that influence the neurons. Do u mean to say that the physical stimuli also contain the phenomenal ones because they are the same?

    But there are technical difficulties in how u would reproduce all the stimuli without using a neural-like network or any other structure. If u did use any structure, consciousness could still be a property of that structure as a whole.

    *Nevermind i get it now. If the structure surrounding the neuron was different, yet the stimuli it sends to the neuron the same, then a different experience would imply that the experience is generated by more than the neuron and its impulses.
    Last edited: Feb 4, 2007
  20. Feb 6, 2007 #19
    If a microbe has a reaction on it's environment, for example it moves acc. to light conditions or other conditions, then in some sense the microbe is "aware" of light. But then this "awareness" is not to be confused with consciousness, since then everything is consciousness. There is of course no well-defined border between the non-living material world and the living material world, and consciousness and unconsciosness. Is a virus living?
  21. Feb 7, 2007 #20
    That, in my view, is the key point.
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