Thomas Nagel: Thoughts Are Real (2013)
newyorker.com
newyorker.com
https://duckduckgo.com/?q=nagle+%22to+be+a+bat%22&t=fpas&ia=...
https://en.m.wikipedia.org/wiki/What_Is_It_Like_to_Be_a_Bat%...
> Nagel famously asserts that "an organism has conscious mental states if and only if there is something that it is like to be that organism—something it is like for the organism."[2] This assertion has achieved special status in consciousness studies as "the standard 'what it's like' locution."[3] Daniel Dennett, while sharply disagreeing on some points, acknowledged Nagel's paper as "the most widely cited and influential thought experiment about consciousness."
It's fascinating just how vast the gap is. There is seemingly no theory of consciousness that has any testable hypotheses. It's quite engaging to hear some of our most public intellectuals talk about what to make of that.
Imagination is pretty much the only thing that fills that void today.
Some of my favorite speakers on the topic have been Dennett, Hoffman, Tononi and Penrose.
Just look at some of the contributors on the playlist below! And they know almost as little as I do. It's a fun and mindbending topic.
https://www.youtube.com/watch?v=fh7rCV0zi1Q&list=RDCMUCl9StM...
You find it on Researchgate and such, start from a paper and chase down the citations.
The perfect place to prove that is by putting a few citations in your comment. Better to show than tell.
You may start here, follow the citations and their references.
https://www.researchgate.net/publication/221703137_Thermodyn...
He gave a talk organised by The Royal Institution that talked about case studies that explore where consciousness comes from.
I hope this is helpful.
Never trust entirely anything about consciousness or physics that's not boring and downright indecipherable to the layman.
Or was consciousness-created reality all made up on the spot on the birth of the first conscience?
And how has it been kept consistent through the life of all different consciences?
I think the simple fact that, for example, separated tribes of people have lived for millennium within a physically identical world is kinda a dead give-away that reality lives independently of consciousness.
... and the good old "visual illusions therefore 'anything'". About the level of argument sophistication I expected.
https://ndpr.nd.edu/reviews/mind-and-cosmos-why-the-material...
https://www.thenation.com/article/archive/do-you-only-have-b...
> In support of his skepticism [about the soundness of scientific explanations of nature], Nagel writes: “The world is an astonishing place, and the idea that we have in our possession the basic tools needed to understand it is no more credible now than it was in Aristotle’s day.” This seems to us perhaps the most startling sentence in all of Mind and Cosmos.
Nagel doesn't seem to give science credit where credit is due.
I find Daniel Dennett a much more interesting read because he actually wrestles with the philosophical implications of the scientific revolution, rather than rejecting scientific naturalism basically because it doesn't "feel right".
From Dennett's work I recommend Darwin's Dangerous Idea, especially the discussion of "cranes" and "skyhooks". Dennett says that, according to evolutionary theory, the complex structure of the world is built from the bottom up by a sequence of cranes (upon cranes upon cranes...) rather than being dropped from the mysterious, omnipotent heavens by "skyhooks".
I mean, this stream of sensations : Sights, sounds, tastes, feelings - and yes, thoughts.
No, thought does not get a special role here. Except in that we consider it to be special. And we use it to map, narrate and explain everything. We really like "meaning".
We use thoughts like this. We associate this thought with that sight (ex "that looks like a horse"), or this thought with that smell (ex "smells like cookies"), or this thought with this other thought (ex "it logically follows..."). I mean we assign meaning. We map stuff.
But no, thought is not inherently special. It's just one more grape on the perceptual vine.
And all those perceptual/sensational/experience-things are all equally real, as far as I can tell.
We don't have such doubts about any other organ. For instance if someone's pancreas is damaged or needs to be removed, we accept readily that this person will no longer be able to produce insulin by themselves anymore. We don't search for some alternate metaphysical explanation for blood sugar regulation.
It's similarly easy to observe A/B tests vis a vis the brain's role in consciousness.
There is a reason this is a philosophical question, and not purely a matter of science. The reason consciousness is special is because we viscerally experience it in a way that is undeniably more significant than any discrete physical observation (such as your example of insulin production). Of course that doesn't prove anything one way or the other, but to unilaterally declare that consciousness is purely a result of mechanical and chemical biological processes is quite a leap and not something that is easily falsifiable.
For empiricists and other logically-minded folks the idea that reality begins and ends with the physical world can be comforting—after all, that would mean that everything could likely eventually be explained through physical observation and continued rigorous application of the scientific method. However this line of thinking also relies on faith just as religion does: the faith that our perception of reality is representative of the whole of reality and that there is no facet beyond the reach of a cleverly designed experiment.
I am of the opinion that it is hubris to declare one way or another. It's easily conceivable to me that the reality we see and experience is but a reflection of a deeper reality which our meat-sack senses and ideas can not penetrate, but that nevertheless exists and interacts with us.
However that definition is tautological and is distinct from the idea that consciousness arises from neurons firing, which is what most physicalists are taking as the cause of consciousness.
But I don't even think you have to resort to that level of "faith" in physical reality to be fairly confident that the brain is sufficient to explain the mind:
1. The human mind is always co-located with a reasonably well-functioning brain, and has never existed anywhere else.
2. Disrupting the physical/chemical function of the brain dependably and predictably disrupts the function of the mind.
3. We can even sub-locate component functions of what we would consider the mind to sub-regions or processes of the brain.
4. The structure and function of the brain seems to be sufficiently complex to give rise to such a complex phenomenon.
If we saw that fact pattern in any other domain, we wouldn't feel the need to look farther for alternate explanations.
If we had a CERN for the science of mind, it would be building an artificial brain and using it to replicate consciousness.
The key question here is "what gives rise to the experience of consciousness?". Everything you described is about the mechanics of cognition, but it does not explain the qualia of consciousness, or why we are not p-zombies. This is a very hard problem to chip away at from a scientific perspective.
Do you believe that if we were capable if making a replica of a brain that performed all the same functions in silicon, and had the same computational capacity that it would be conscious? Why or why not?
Why do you think so? What makes you think subjective experience is not just another type of brain function, like smell, taste or value judgement?
> Do you believe that if we were capable if making a replica of a brain that performed all the same functions in silicon, and had the same computational capacity that it would be conscious? Why or why not?
Yes I do believe so. I believe that consciousness is a function of our nervous system, so if you could make a perfect copy, put it into the same state, and gave it all the same inputs and outputs, it would be conscious.
However I think we're very far from that. the functions of the brain depend on complex and diverse sub-cellular processes which current models don't scratch the surface of replicating with any kind of fidelity, so I think it will be quite some time before we can test this hypothesis.
To pose a similar question to you, if you don't think a perfect replica of the brain would give rise to consciousness, what do you think would be missing?
The key here being "not just". The reason is because there is no conceptual identity between subjective states and brain functions. They're entirely different things. This doesn't mean brain states aren't involved. It means a reduction or identity can't be stated as the solution without explaining how the subjective comes from it.
This is basically the modern version of John Locke's secondary qualities of perception (color, taste, etc) not being the primary qualities of objects (number, extension, etc). Neurons have objective qualities identified in science. But how they have secondary qualities is the big mystery.
It's because subjective experience (SE) cannot even be defined in physical terms. Or any terms, really. Instead of any definition of SE, all that's on offer are ostensions that will direct a reader's attention to his own SE if he's having it. Such as:
Descartes: SE is what you're absolutely certain must exist, even if everything else is an illusion.
Nagel: SE is "what it's like to be _____".
Nagel again (same paper, but not quoted enough): It [SE] is not captured by any of the familiar, recently devised reductive analyses of the mental, for all of them are logically compatible with its absence. [italics mine]
What makes you think that it's undefinable, rather than that we're just not capable of defining it?
For instance, as human beings we cannot ever really understand systems like the weather, or the economy. We can understand some of the component forces involved, but there are too many things interacting for us really to wrap our minds around how the whole thing moves.
Similarly, we now have a proof for the 4 color problem, but it had to be provided by a computer, because the number of cases involved in the proof was not really within the grasp of the human mind.
As humans, we can basically hold 7-10 things in our mind at one time. So in order to "solve" something, we need to be able to break it down into a maximum of 7-10 component parts at any one time. What if it's the case that the physical origin of subjective experience is perfectly obvious, but it would require a consciousness with the capacity to consider 1000 independent neural processes at the same time to see the solution?
> It [SE] is not captured by any of the familiar, recently devised reductive analyses of the mental, for all of them are logically compatible with its absence.
I don't really get this one. How is it that the empirical explanation of subjective experience is compatible with its absence?
Descartes described the clearest identifying property of SE: it's absolutely certain to exist. Since absolute certainty lies outside the scope of science: science can't define what SE is, it can only describe what SE does.
Science doesn't rule out the philosophical hypothesis known as "illusionism" (advocated by Keith Frankish), that SE is a delusion.
If you, skohan, have SE and have correctly identified it: its nonexistence will be inconceivable to you. Are you there yet?
This is where Nagel is wrong. Mental activities don't map directly to brain functions, but this doesn't at all mean that they are not part of the physical world.
https://www.quantamagazine.org/mental-phenomena-dont-map-int...
Computers have mental activities too, simple ones, but we are not tapping into a different realm to make that happen.
Would be cool though, because both computers and brains are constrained by that pesky thermodynamics. Scratch that. They are defined by it. In fact you don't even need computers or brains for lifelike behavior. Any system responding to a stochastic driving signal can be interpreted as computing. Making a predictive model of the environment equals to using available energy efficiently.
https://www.quantamagazine.org/how-life-and-death-spring-fro...
That's begging the question as to whether awareness arises out of the physical world. You're assuming mental activities arise out of computations occurring in the physical world, when whether or not this is the case is in fact the question.
Of course we think that humans are special, but a gerbil, a cauliflower plant, even a metal spring does this. Granted a cauliflower can do much more than a spring, but then a gerbil can do more than a cauliflower.
https://nautil.us/issue/104/harmony/plants-feel-pain-and-mig...
Why? Because the person in the computer, being a faithful simulation of a human mind (or some AI analogue), will say they feel exactly the same mental things as real humans, down to the most minor detail. You then see they are just software, and say it's impossible to prove they feel the subjective experience they claim to feel.
Then they say you're just a dude and it's impossible for you to prove you feel this subjective experience you claim to feel.
There's no way out. If it's possible _at all_ to have self-aware software, they will have exactly the same claim to consciousness as yourself. Which is: I can't show my mental state to anyone and you need to take my word for granted.
The argument made in that sentence is something like: if we come up with a description of how a bunch of photons interact with an eye to trigger a series of chemical reactions that lights up a bunch of neurons in a way that is proven to represent some mental image then, per Nagel, even if we achieved this, our explanation of sight would be missing something. The thing it would be missing is the subjective experience of seeing, something most of us are familiar with.
Nagel isn't saying that this subjective experience is something other than physical or material. He's saying that the brand of materialism currently in vogue cannot account for this subjective experience and so needs to be revised.
I'm not taking any sides here, but just making a point.
The different parts of us do their jobs and a coherent picture is created. The most coherent picture is the first person view, but it is a fabrication. It's like a news report. The perceived self is a part of a stitched together story, not a central agent. The whole brain is the agent, however we only remember the story. The story is what ends up as a memory. The perceived self exist because I is an important context needed later for prediction, like the dimensions of your body and a lot more in a social environment. But your perceived self is not the actual you, just as your perceived world is not the actual world.
The general idea is that the signals from the nodes are processed and fed to the hippocampus to create an episodic memory engram, which reactivates the nodes that contributed the signals. This is when subjective experience happens, after all the work is done. Granted the next time the nodes can rely on what happened before, so we are not philosophical zombies, we don't passively experience it all, but the central agent is only a useful theatre, we are multitudes under the veneer.
The extreme complexity of this theory of the world is of course irrelevant to the kind of people whose end goal is to put art on the same footing as science not only in abstract value (which it surely does) but as an actual method for knowing the world (which is preposterous).
To be clear, if we accept the existence of a non-physical mental realm, we have the monstrous problem of explaining how these two interact, as there are numerous correlations between the two.
But the origins of the mind in the body and brain are not beyond scientific exploration, and we have been making progress towards them - only baby steps so far, but already too much to keep believing in anything like dualism. In fact, mind/body dualism has not been taken seriously in any scientific circles for at least a hundred years, but it persists in certain philosophical circles, with silly thought experiments such as 'p-zombies'.
I suspect a lot of the most interesting investigations of the next few hundred years will be in sorting out whether this is the case, and if so, how it all works.
However, I am not aware of a single argument for dualism beyond 'we don't yet know how it works' or 'I can imagine a p-zombie/qualia therefore it must exist and it disproves that the mind is something like computation'.
>Since neither physics nor Darwinian biology—the concept of evolution—can account for the emergence of a mental world from a physical one, Nagel contends that the mental side of existence must somehow have been present in creation from the very start.
I mean Tesla cars can form a neural network model of the world around them. I don't think you have to go beyond physics to explain this stuff.
I doubt it.
The reductio absurdum of Nagel's theorem is this: existence of everything in the universe is given existence by human imagination. So if all humans were to die off, everything that remains would, what, disappear?
That isn't metaphysics. It's anthropocentric solipsism.
> In a way you can say evolution is both true and it's not
Why?
> for all we know following the things that are tried and proven is the more practical thing to do, right?
What?
> Like, when it comes to Pokemon for example, I just looked up that Pikachu evolve to Raichu. But wait does he really? Or isn't that just bunch of fabrication too? Well for all intends and purposes that's how it works right?
?????
Similarly for us humans, each of us is tiny tiny infinite small part of the whole thing, and the "whole thing" is what creates the universe. In that sense it's not really real, but for us, from our perspective as individuals, it is real. Or as real as it's going to get, for now. We know our world behaves in predictable ways, we can analyze, measure, know of the laws of physics, and we'd be foolish not to abide by its rules. Like they say that train coming down the tracks is very real and you wouldn't want to step in front of it.
But at the same time you'd be foolish to fixate completely onto material world. I believe there are some things science will never be able to answer, consciousness is one of them. I mean it's something you have to decide for yourself, think about it, whatever it is you want to believe in. No one give you the ultimate truth here. The thing is though, all things considered, consciousness not arising from our physical reality, is the approach to take if you want to learn more about this stuff.