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by jemmyw 985 days ago
There are plenty of reasons to believe it's physical. I mean, in some ways I can't believe I'm having to write "there are no ghosts" to a technically minded community.

If consciousness was not physical then where is it? Why would it switch on and off with physical changes to brains? Why would you be able to get altered states of consciousness with chemicals, disease and age? Why would be be able to marry some conscious activity with MRI scans?

There's quite a few bits of evidence to suggest it's physical even if we don't know how it works. There doesn't appear to be any evidence of another... what is a non physical process anyway? Surely there's only two options: the physics we know and the physics we don't know?

4 comments

Yeah I’m not sure why someone would argue that consciousness isn’t physical. Take a conscious person and knock them hard in the head. Interesting, their consciousness is altered. Take drugs? Check it out, consciousness altered. People who experience head trauma have their personality permanently altered. In the course of life you will likely directly observe the effects of physical injury on a person’s consciousness, just due to how often that kind of stuff happens.
> Yeah I’m not sure why someone would argue that consciousness isn’t physical

Reading the comments, one thing that's been unsaid is whether each person discussing is religious/spiritual or not. My guess is that if you are religious then the idea of there being another layer in the universe goes without saying, and if you are not then it's ridiculous.

It's probably a waste of time debating across that line.

For me it has very little to do with religiousness but rather calming down some rather frequent panic attacks in the middle of the night. The fact that thinking the wrong thing can erase your consciousness while thinking it, doesn't help from the group that believes thinking the wrong thing erases consciousness.
The difference is people like you mean consciousness = "consciousness as the average human experiences it", whereas others include every single potential conscious experience, including the delibitated one. From your perspective, a knocked out human isn't conscious the same way a corpse is not conscious, because he does not conform to the average human experience.

Meanwhile others think that the knocked out human and the corpse and the average human are all conscious, but they experience their respective consciousnessess aka the consciousness of an average human, knocked out human or corpse. You could say that this is just a disagreement in what the word conscious means.

>Why would be be able to marry some conscious activity with MRI scans?

Does the activity cause the changes on the scan or does the changes in the scan cause the activity? How does neuroplasticity result in physical changes to the brain through, for example, cognitive behavioral therapy? Do the thoughts alter the physical structure or does the structure cause the thoughts even before the structural changes?

Internal feedback loops. Activity from the existing structure further modifies that structure. That activity is that thoughts are. So sure but it's all physical.
That doesn't make any sense. If that's the case, the physical change should precede the changes in thought patterns.

Also, physicalism is about as empirical as falling in love. It's far from definitive, proven, fact.

There's no chemical emission that can force someone to have an exact thought, dream, or inner dialogue.

Think about it like in the case of computers. The claim we are making is that our thoughts are essentially the same kind of things as the states that arise in a piece of software. And we already know that there exists today computer software which can be asked to modify itself through its own APIs.

Basically the way we view this is that CBT works kind of similarly to using the JVM APIs to modify some pieces of the running Java program to try to fix a bug. In this analogy, Psychiatric medicine would then be more like directly modifying the bits in RAM that represent a certain piece of executable code. They are both physical modifications ultimately, just working at different levels of abstraction.

They are not physical alterations. The software doesn't change the physical structure of the FPGA or CPU it's running on. It is not creating new gates or transistors or how they're physically connected, only utilizing the existing physical connections differently
Electromagnetic fluctuations in the wires are every bit as physical as the wires themselves.
There are always physical changes happening. External stimuli, and time based internal changes.

> If that's the case, the physical change should precede the changes in thought patterns.

Not precede, are. These aren't separate things.

> There's no chemical emission that can force someone to have an exact thought, dream, or inner dialogue.

How do you know that to be the case? It seems likely to me that an exact set of sufficiently complicated inputs and stimuli could generate an exact thought. Actually doing so would be too complex to figure out, but many physical systems are like that.

If it seems likely to you, then you're not as much of an empiricist as you claim
The idea that consciousness is physical doesn't mean it's mechanical. Physical world is made of fields with no clear boundaries, while mechanical system are made of isolated deterministic and immutable parts.
The difference is that you do not experience ghosts, but you do experience conciousness.

>If consciousness was not physical then where is it?

We can invert this and ask, if physicality is not ideal, then how do we come to know it?

>Surely there's only two options: the physics we know and the physics we don't know?

The third option is that physics is unable to interrogate itself.

> We can invert this and ask, if physicality is not ideal, then how do we come to know it?

Why would we ask that? Not ideal for what? It just is.

> The third option is that physics is unable to interrogate itself.

This is likely true. We are the product of physics and we can only delve so deep. It might be that we cannot see to the most fundamental level(s). That's not a third option though, that's just the state of any scientific investigation at any point of time. However, given all we have learnt so far, what we don't need to do is invent new gods for the levels we cannot see or the things we cannot yet understand. I mean, people will, evidently, but that's all just wishful thinking.

Meanwhile there is slow progress to piece together how the brain works. My opinion is that we will figure it out but the answers about consciousness will be unsatisfactory. Just like right now, given the current understanding of physical processes even taking into account quantum systems having probabilistic outcomes, we have no free will. It's an answer, I find it a compelling one, but most folks don't like that answer.

> Why would we ask that? Not ideal for what? It just is.

I'm pretty sure GP was using "ideal" in the sense of "made up of ideas", as in the philosophical concept of idealism, which is essentially the opposite of materialism: idealism is the position that the real world is that of the mind, and physics and the physical world is an emergent property of our minds, not the other way around.

Not that I think this is a real coherent position worth discussing.

> Not that I think this is a real coherent position worth discussing.

Why is it not a "real coherent position worth discussing"?

Because to me it seems that if it were made consistent, it would extend into solipsism. And if it does, I don't think it's worth discussing then.
“the universe is the extension of the self” is precisely the idea we are talking about.

IMHO it is the only thing worth discussing.

And yes you can derive new “physics” with this idea alone.

What is inconsistent about non-solipsistic idealism?
Thanks that was insightful