Can consciousness exist without any brain at all?

[AverageBozo]

In this topic, what does it mean to be 'conscious'? Responding to stimuli (observable)? Experiencing awareness (only observable by the experiencer)?

I presume we're talking about phenomenal consciousness = subjective experience.

A completely brainless human or nonhuman animal doesn't only lack phenomenal consciousness but also all other mental faculties such as perception, cognition, and memory; so being brainless entails being mindless.

Some animals (eg, sponges, cnidarians) function without a brain. How it can it be assumed they lack any kind of phenomenal consciousness?

Robots can have perception, aspects of cognition, and memory, without having a brain (depending on what qualifies as brain).

Where can lines be clearly drawn between what can and can't have phenomenal consciousness (or between what must and must not have phenomenal consciousness)?

As you imply, such a line cannot be drawn without a definition of consciousness as well as the definition of what qualifies as brain.

[AverageBozo]

Can consciousness exist without any brain at all?

Consciousness cannot exist without 'memory'. And if memory (memory function) is confined within the brain, then NO, consciousness cannot exist without the brain that possesses a memory function.

Consciousness is the bodily (brain) experience of 'recognition', made possible by memory. --- No memory = no recognition = no consciousness.

What you say makes sense. However, on further reflection I wonder if memory is necessary for consciousness, or for awareness anyway.

I thought of a human experiencing something for the first time, say the sharpness of a rock or the image of a coconut tree. There’d be no memory for that first encounter, but there would be an awareness even without memory of a previous encounter. The edge of the rock might look and feel sharp. The image of the coconut tree might appear colorful.

I’ve come to think that awareness can occur without memory. Recognition is a much more efficient process than mere awareness, but awareness can occur without recognition.

All depends on what is a satisfying definition for consciousness.

[Consul]

Some animals (eg, sponges, cnidarians) function without a brain. How it can it be assumed they lack any kind of phenomenal consciousness?

Their behavior and its inner causes can be explained without any appeal to P-consciousness. Sensorimotor skills do not require a central nervous system and not even a nervous system at all.

"Most researchers accept that even quite complex perception, cognition, and control of action can go on entirely 'in the dark'."

(Godfrey-Smith, Peter. "The Evolution of Consciousness in Phylogenetic Context." In The Routledge Handbook of Philosophy of Animal Minds, edited by Kristin Andrews and Jacob Beck, 216-226. London: Routledge, 2018. p. 220)

Robots can have perception, aspects of cognition, and memory, without having a brain (depending on what qualifies as brain).
Where can lines be clearly drawn between what can and can't have phenomenal consciousness (or between what must and must not have phenomenal consciousness)?

Functionally defined, a brain is a central processing and control unit. Of course, the CPU/CCU of an AI robot is not organic "wetware" but inorganic hardware.

Whether artificial experience (P-consciousness) is physically possible in addition to artificial intelligence (cognition/perception) is a highly contentious issue.

As for the distribution of natural experience (P-consciousness), a very plausible line can be drawn between brained animals and all other kinds of organisms. That is, being a brained animal is necessary for (natural) P-consciousness, but it may not be sufficient for it, because it may be that only more highly developed brains are capable of realizing P-consciousness. Actually, it's unlikely that the evolutionarily first and most primitive brains as we find them in flatworms called planarians can generate subjective experience.

Planaria Nervous Systems: http://www.scholarpedia.org/article/Planaria_nervous_system

[AverageBozo]

My brother often told me that he had more brains in his pinkie finger than I had in my entire head. I don’t get it. He must’ve been right

[RJG]

Consciousness is the bodily (brain) experience of 'recognition', made possible by memory. --- No memory = no recognition = no consciousness.

What you say makes sense. However, on further reflection I wonder if memory is necessary for consciousness, or for awareness anyway.

I thought of a human experiencing something for the first time, say the sharpness of a rock or the image of a coconut tree. There’d be no memory for that first encounter, but there would be an awareness even without memory of a previous encounter. The edge of the rock might look and feel sharp. The image of the coconut tree might appear colorful.

Memory is composed of sensory associations. We "recognize" by re-experiencing the sensory associations that are held in memory.

For example, imagine our very first experience of "cat". Imagine our kindergarten teacher holding up a big picture of a cat (visual experience) and then saying "c-a-t" (auditory experience), a memory was then formed. This memory consists of the association of sensory experiences (visual to audio). -- So now, whenever we hear the sound "c-a-t" we automatically re-experience the visualization of the cat ...and vice versa, ...all thanks to memory that holds this sensory association.

Language is a good and obvious example of "recognition" (re-experiencing sensory associations held in memory). Without memory (and therefore recognition) we would not have any thoughts; for if we did, we would be unable to understand the language in which these thoughts spoke to us.

I’ve come to think that awareness can occur without memory.

Not possible. For what (specifically) is it that you are aware of?

Without 'something' to be aware of there can be no awareness. (akin to - without something to read, there can be no reading). --- Without memory, we are just blank slates.

...awareness can occur without recognition.

Not possible. Without 'something' to be aware of, there can be no awareness (...without something to read, there can be no reading).

[AverageBozo]

You are right RJB and I agree with your post.

However, I would go one step further, as the following example denotes.

If my hand grasps a glowing ember, I may not have a word for heat and I may not remember the experience of heat, but I will certainly experience heat. And if I am conscious, I will certainly be aware of the experience.

But I am quibbling. The relationship between cognition and memory-dependent re-cognition is trivial and irrelevant if consciousness is defined as requiring recognition.

And I am more than willing to accept such definition going forward from here. And this means that I am in agreement with your position, RJB, both here and in any other thread.

[psyreporter]

According to the expert opinion of psychiatrist and psychoanalyst Carl Jung (founder of analytic psychology), it is possible.

(2020) Carl Jung on the possibility of consciousness without a brain
… philosopher Henri Bergson is quite right when he thinks of the possibility of relatively loose connection between the brain and consciousness, because despite of our ordinary experience the connection might be less tight than we suppose. There is no reason why one shouldn’t suppose that consciousness could exist detached from a brain . . . the real difficulty begins … when you should prove that there is consciousness without a brain. It would amount to the hitherto unproven fact of an evidence that there are ghosts.

I think that this is the most difficult thing in the world to create an evidence in that respect entirely satisfactory from a scientific point of view . How can one establish an indisputable evidence of a consciousness without a brain?

I might be satisfied if such a consciousness would be able to write an intelligent book, invent new apparatuses, provide us with new information that couldn’t possibly be found in human brains, and if it were evident that there would be no high power medium among the spectators.
https://carljungdepthpsychologysite.blo ... t-a-brain/

[Consul]

According to the expert opinion of psychiatrist and psychoanalyst Carl Jung (founder of analytic psychology), it is possible.…

Brain- or even body-independent consciousness is conceivable, because our psychological concepts arose historically in logico-semantic isolation from our physical/physiological concepts; so we can coherently think about minds without having to think of them as things which depend on bodies and brains. But this conceptual possibility of brain-/body-independent consciousness isn't the same as a real, natural possibility.

[Consul]

...awareness can occur without recognition.

Not possible. Without 'something' to be aware of, there can be no awareness (...without something to read, there can be no reading).

Awareness is always cognition or perception of something, but not always recognition. You cannot recognize what you haven't cognized or perceived before.

[Consul]

Brain- or even body-independent consciousness is conceivable, because our psychological concepts arose historically in logico-semantic isolation from our physical/physiological concepts; so we can coherently think about minds without having to think of them as things which depend on bodies and brains. But this conceptual possibility of brain-/body-independent consciousness isn't the same as a real, natural possibility.

As Stephen Yablo puts it, "conceiving involves the appearance of possibility"; but there can be "illusions of possibility", so an intellectual appearance of possibility needn't correspond to modal reality, i.e. to what is possible and impossible in reality (especially in natural reality), as opposed to what is possible and impossible in thought.

[RJG]

...awareness can occur without recognition.

Not possible. Without 'something' to be aware of, there can be no awareness (...without something to read, there can be no reading).

Awareness is always cognition or perception of something, but not always recognition.

Not so. It is not logically possible to be aware of something without recognition. You can't be aware of something if you don't "know" you are aware of something. -- If you recognize nothing, then you are a blank slate; then you are aware of nothing.

[Pattern-chaser]

Brain- or even body-independent consciousness is conceivable, because our psychological concepts arose historically in logico-semantic isolation from our physical/physiological concepts so we can coherently think about minds without having to think of them as things which depend on bodies and brains.

Our minds are embodied. This has always been the case. No matter how we might think our thoughts are divorced from our bodies and bodily functions, they are not, and never have been.

But this conceptual possibility of brain-/body-independent consciousness isn't the same as a real, natural possibility.

A possibility is something that is (or might be) possible. In that sense, all possibilities are the same: they are possible.

[Consul]

But this conceptual possibility of brain-/body-independent consciousness isn't the same as a real, natural possibility.

A possibility is something that is (or might be) possible. In that sense, all possibilities are the same: they are possible.

Yes, but not unqualifiedly, because there are different kinds of possibility.

[Pattern-chaser]

But this conceptual possibility of brain-/body-independent consciousness isn't the same as a real, natural possibility.

A possibility is something that is (or might be) possible. In that sense, all possibilities are the same: they are possible.

Yes, but not unqualifiedly, because there are different kinds of possibility.

A possibility is something that could be true, or that could exist, as opposed to something that is true or does exist. Our estimation of possibility (or probability) could be wrong, of course. But beyond that, possibilities are just possibilities, no?

[Consul]

To quote myself: "If having a (C)NS is unnecessary for having subjective experiences, what is physically necessary for it? Being a living organism? But why stop there? Why should life be a necessary condition for consciousness? There is a slippery slope to transbiological panpsychism; and the only line between subjects and nonsubjects of experience that can be drawn nonarbitrarily in the light of our knowledge of nature is the one between brained animals and all other physical things."

Of course, substance dualists and substance spiritualists (spiritualist substance monists) will reply that nothing is physically necessary for having consciousness or a mind, because subjects of experientiality/mentality are immaterial substances.