
What Makes Brains Conscious?
Closer To Truth
Exploring the Mind-Body Problem and Neural Correlates of Consciousness
This chapter delves into the mind-body problem and the search for the neural correlates of consciousness. The speaker discusses how different coalitions of neurons in the brain compete for attention, resulting in conscious experience. They also raise questions about tracking and identifying these neuronal coalitions.
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Speaker 3
Alright, listen, listen. I've got to interrupt. You've got to let me interrupt, because I've got to make a really important point. Listen, I've never done psychedelics. And I don't think I ever will but like if i did it's like i kind of imagine sitting down saying like you know like from state changes and time and temporal and concrete and you know like all these words are just like going around and it's like how did we end up here that's
Speaker 1
this beauty of this paper did
Speaker 3
you when you said you said concrete earlier instead of physical like do they mean the same thing concrete and physical i don't even know yeah
Speaker 1
so we'll get into this in the next section of the paper where they make sure to make the distinct i think it's next section where they make sure to make the distinction between like is the universe completely physical all right let's do
Speaker 3
it but let me just pop some mushrooms first all right well
Speaker 1
is the universe completely physical is not something they're just assuming they're just gonna say all we're talking about is the physical universe but in this context we had to not say physical and the reason we have to not say physical is because abstract objects implement all physical objects right and so we're talking about things that are not physical that implement the physical or
Speaker 2
we're considering them at least
Speaker 1
yes yes that's in this conversation wait
Speaker 3
so you have objects some of them are physical Yep. Like my phone. Or
Speaker 2
like the hole of a donut. Right.
Speaker 3
Okay. And some are abstract. Like numbers. Right. And abstract. So for the universe to be computable, abstract objects need to implement all physical objects yes that's
Speaker 2
the question yeah that's what what that's what they're asking is could that happen happy
Speaker 1
to translate that to myself yep
Speaker 2
that's
Speaker 1
a lot of what we're doing yeah and so the reason i say concrete instead of saying that they're physical is i don't know that the implementation itself would be physical it creates the physical there's like
Speaker 2
a floor to physicality it's
Speaker 1
the thing that underlies the physical oh
Speaker 3
because we're we're oh because we're implementing the universe that's right we can't implement the universe in the universe yes well
Speaker 2
well well that's a question that they don't engage with. They should have engaged with that question. That's a fascinating question. But
Speaker 3
that's not what we're talking about, right? So they're saying... We could talk
Speaker 2
about it.
Speaker 3
It's like we need another word because we're already using physical to describe what we're implementing. To mean the stuff in the universe. But how do we actually implement the implementation well well we can't use physicals so we call it concrete that's
Speaker 2
right well
Speaker 1
yeah so an example of something that could be concrete but not physical i'm not saying these things exist i'm just giving examples souls oh triangles
Speaker 2
triangles
Speaker 1
are abstract they're not concrete triangles
Speaker 2
are concrete no they're
Speaker 1
abstract they're
Speaker 3
phrygian that's
Speaker 2
a throwback
Speaker 1
a soul would be something that is not physical like descartes soul would be something not physical but concrete uh it would not be abstract
Speaker 2
like the number two why is a soul concrete i don't get that that doesn't make sense i
Speaker 3
my soul is leaving my body in this in this conversation honestly abstract
Speaker 1
right are unchanging timeless causally inert things causally inert and descartes soul is not any of those things uh
Speaker 2
so it's it's not like souls in the... Dark souls. Metaphysical sense, it's souls. Descartes has this definition of a soul.
Speaker 1
No. Souls in the metaphysical sense is Descartes' souls. Yeah. But souls exist in time, right? They undergo changes, and they can affect something.
Speaker 2
You are using a... I am unaware of the soul
Speaker 1
as in mind if you want to like yeah descartes idea of yeah descartes
Speaker 2
animating the mind essence the
Speaker 1
non-physical part
Speaker 2
i've got a mind to move on to the next section
Speaker 1
do i have a mind mind as distinct from brain yeah right that's what
Speaker 2
we're talking about well the next section talks about brains we're at the halfway mark is
Speaker 1
no
Speaker 2
way yes
Speaker 1
we're
Speaker 2
at the halfway mark two
Speaker 1
hours in i should have
Speaker 3
taken so and it never mind they're kicking in is
Speaker 1
the universe computable is the second question yes right so we had is the universe a computer well we did not we did just determine wait wait wait you need to say tm you need to say tm right tm
Speaker 2
yeah yeah
Speaker 1
yeah from now on if i say computer i only mean tm because that's all i think well
Speaker 2
i don't not for me i will i would never yeah i
Speaker 1
am saying it for me um is the universe computable now computable here is computable by a turing machine right but we can i'm going to start probably quoting this a computable system is a system whose behavior could be computed by an idealized human
Speaker 3
computer. This
Speaker 1
is the definition. That's what TM means. Yes. Is computable by an idealized. Right.
Speaker 3
But wait, wait. An idealized,
Speaker 1
does that mean like perfect?
Speaker 2
Yeah, they're going to unpack that. Well,
Speaker 1
we've already unpacked that.
Speaker 2
they unpack it more yes
Speaker 1
i'm sure that they do but uh i want to like idealized as in has an infinite amount of time etc that's that's really what we're talking about here doesn't get tired that
Speaker 3
human computer the
Speaker 1
human computer is idealized in that no limit is placed on the amount of time available to the human computer nor on the quality of the paper and pencils available idealized human computers live indefinitely long and never get bored which i just love that they never get bored it's not that they it's not that they never just stop right you could have just said they never stopped doing the computation. Because they could just like still keep going, but be bored, but not. They're also having fun. That's key. If your computer's not having fun, it's not a TM. Right.
Speaker 2
There's actually quite a few of these sort of like flavorful, you know, dehumanizing descriptions of the idealized human computer.
Speaker 3
They're funny. They're funny.
Speaker 2
Yeah.
Speaker 3
But I find this really confusing when it does this because like i'm like i don't think ah because we so much we're talking about well a computer tm needs to be deterministic right but then it says like for example like an idealized human computer, right? Yeah. And, like, is a human deterministic? Okay, hold on. The human is following a series of
Speaker 1
steps, and those steps are the things that are deterministic, not the person themselves. That's
Speaker 2
a good distinction.
Speaker 1
Okay. Right. The steps are deterministic.
Speaker 3
So a step could be pick a random number between one and ten. No, because that would be a non-deterministic thing.
Speaker 1
You could say, do this pseudo-random computational process, and that's what we do with our computers. We give a pseudo-random computational process. That's fine. That's allowable. you couldn't say is sample the current you know we have these like true random ways or whatever from the universe if you tried to say sample this random thing from these sorts of things you would now end up having to go well is that deterministic or not well it depends on if the universe is deterministic right so it could be allowable if the universe is deterministic, but we don't know. So I'm like, that's fair enough. I get that. So why? Yeah. Okay, I just want to give like a justification for why here, because I feel like this is something that's like a sticking point that may even not be clear. So like one, one reason that we're sticking to this is because we're trying to be a little bit historically accurate and, you know, trying to say what Turing said. That's one reason. Not a very good reason, but one reason here. The other reason is that this definition that Turing offered us ends up going into so many different areas that really matter for mathematics, for practical upshots of what we can do. Yeah, yeah, yeah. That makes sense. There's lots of things that if they are computable, we are able to know them and find answers to them. That if they are not computable, we have not been able to find answers to them. So this actually has like a real practical import. TM. Yeah, yeah. When I say computable, I am always meaning the definition here of like Turing's.
Speaker 2
Lou was making him a bim bam reference. I
Speaker 3
don't even know what that is.
Speaker 2
Arcade just laughed. There you go. That's that's that's all you need to know.
Speaker 3
Okay. Nice. In jokes. There we like I
Speaker 1
said before, when we find something that's uncomputable, it means practically we have not been able, if it's uncomputable, we can find approximations of it. We can do things like that. But we're not able to actually find an answer to those uncomputable problems. It's like computational complexity, where if something's quadratic, it's very hard to find an answer for. This is taking that one step further. We can't find an answer for it yeah
Speaker 2
how do you say the name kol glomer of kolmol girl of cola yes
Speaker 1
until you said it i could have told you but now that you've
Speaker 3
put that in my head poisoned his mind you poisoned yeah
Speaker 2
i i find that that stuff fastened like and we're at the two hour mark so we might as well wrap up uh this i i really enjoyed this paper it like we branched off into complexity theory in a way that i i
Speaker 1
can speed run through this section and then we can talk about.
Speaker 2
Yeah, do it. Cause this second section sucks. The second section sucks. The second
Speaker 1
section is gray.
Speaker 2
I have it all highlighted in green. So the
Speaker 1
question is, and again, every time I use the word computable, I mean, computable TM, cause that's how every mathematical thing uses the word computable. So, uh, computable, uh, is the universe computable? And so what we're saying is, could we given the, are the current physics is the universe as it is actually computable, meaning we could make a Turing machine program that would give us the whole answers that could simulate the universe. And it goes through a series of ideas about, well, what if you could have a, a lamp here is one of them that does something uncomputable.
Speaker 3
Yeah. It
Speaker 1
kind of like goes off on these little tangents. I think they're not quite important to us to go through the details. So one example that they give is a lamp that is not a computer, but its flashing behavior is computable. You can imagine a lamp that is just flashing lights, and it's flashing in a certain sequence. I'm imagining it right now. That lamp isn't itself computing anything. Let's just assume that there's something else turning it on and off at certain frequencies. But we could look at it and figure out, is this computable? Or we could just say we know the description. So for example, the lamp could be actually flashing the numbers of pi. So it waits a certain amount of time and ends up flashing pi. And pi is a computable number. And so while the lamp itself is not a computer, its flashings are computable because it's flashing pi. But if the flashings were completely random, literally random in the biggest sense you can mean by random not pseudo random they would not be computable because there's no way that you could simulate that using a turing machine simulate is like it's a dangerous word i think the way they put it i'll not use the word simulate i just think it's yeah randomness is one form of uncomputability if the lamp were flashing randomly its behavior would not be computable because if the human clerk could always predict the behavior at the next second then the behavior would not be random so if something is ran if something is truly random there is no algorithm we could write no machine that we could do that would predict exactly when it's going to happen. And so if it's completely random, we could not make a machine that could predict when the next flash is going to happen with 100% certainty. Right. That's what we're talking about here. So Turing machines can only, you can only predict deterministic behavior. You can't predict undeterministic behavior. And Turing machines aren't the exception. They can't all of a sudden figure out undeterministic things. So now the question is, is the physical universe computable? So the answer depends on what can actually happen in the physical universe. If the physical universe has true randomness, then it's not computable. That's just plain and simple. So we have to go ahead and just assume if we want to say that the universe is computable, it's going to have to be deterministic. Ivan's breathing heavy at me, but this is literally what is... I'm summarizing the article to be clear this is what the article says are you disagreeing this is what the article says or you know i'm not
Speaker 2
disagreeing with what the article says yeah i'm disagreeing with the article okay
Speaker 1
let me summarize what the article says you
Speaker 2
are summarizing what the article says okay i'm
Speaker 1
not stating my opinions so if it's to be computable it would have to be deterministic. Let's just assume that for a second, because if it's not, then it's not computable. All right. So let's assume a deterministic physical universe. Is it computable? Well, there's actually this really interesting idea called accelerated Turing machines. And accelerated Turing machines are a Turing machine that you make a Turing machine and each step that it takes starts getting faster and faster and faster, so that it could take, it could do infinite computation in a finite amount of time. And then the question is, can you make an accelerated Turing machine? And there's this crazy speculative idea by a physicist, Patowski, who says, yes, you could. That if you take advantage of certain things in, it was originally special relativity, but we've moved now to also making it work with general relativity. And you took this black hole known as a slow Kerr hole, and you sent a computer into this black hole. And the black hole, it's able to exist in there because it's a slow Kerr one. This
Speaker 3
paper is crazy.
Speaker 1
We don't know for sure that they exist but we have astronomical evidence that they might. So anyways if you sent it in there relative to the observer some outer world shit time would continue to get faster and faster and faster so you could. you mean outer wilds send in a computer that assuming you can keep it up and running and blah blah blah we're just gonna assume that for a second what did i say it could do relative to some observer an infinite amount of computation in a finite amount of time you said outer worlds and so you could compute uncomputable things outer wilds
Speaker 3
yeah yes it's pretty cool right and
Speaker 1
so if this is true if this is for physically realizable the game that is the comp the universe is not computable which is fascinating okay
Speaker 3
and
Everything I know -- everything! -- comes from my brain. Consciousness, our private sense of inner awareness, is the one big question to which we might find answers.
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