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Old 08-14-2019, 12:14 AM
Max S. is offline
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Location: Florida, USA
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Quote:
Originally Posted by begbert2 View Post
Firstly, the phrase "Nonmaterial claims are nonfalsifiable" is nonsense. The claim "Ghosts are always able to pass through walls, and also they're never able to pass through walls" is definitely falsifiable (and false). One can absolutely logic about the immaterial.
In order to be falsifiable, a claim must be open to refutation through physical evidence. Assuming you cannot directly or indirectly observe ghosts, the above premisses are contradictory but not falsifiable.

Quote:
Originally Posted by begbert2 View Post
And one can determine that the mental state is not suffused with static by observation. As I noted random perturbation could be occurring within the mind, but it clearly doesn't have notable effect. Emotions don't change randomly, beliefs don't change randomly, opinions don't change randomly, knowledge doesn't change randomly. These are observable facts about minds.
First, the only mind I can actually observe is my own. I assume the existence of other minds but I cannot observe them; I can only observe their physical brains and only then in the hypothetical. We can mark the existence of other minds as another assumption made.

I agree with you that mental states are stable - based on my own memory, my own emotions do not change with "wild randomity", nor do my beliefs, opinions, or knowledge. I agree that the mind "is not suffused with static". The part I disagree with is that all changes in mental state flow from causes. You say this is supported by observation, but I don't think it is. I will admit that there are some changes in mental state which have causes.

For example, take the seemingly random sensation of numbness in my left pinky finger this morning. Sensation is a mental phenomenon, but in this case, it had a physical cause: an overtight wristwatch band. My understanding of anatomy is that the tight band applies pressure to the wrist, which compresses the tissue in and around Guyon's canal. This in turn restricts blood flow in the little arteries supplying the ulnar nerve with blood. The neurons, starved of oxygen, switch to anaerobic metabolism which produces less ATP. With insufficient ATP, the nerve's ion transporters eventually malfunction. This causes the neuron to send the wrong signals up the nerve and to the brain. Exactly where, when, and how this produced a sensation of numbness in my mind is unknown and possibly unknowable without making further assumptions. I could design an experiment where I intentionally over-tighten my wristwatch band to induce an experience of numbness, to reinforce the hypothesis that tightening of the band causes a sensation of numbness. I won't do so because I am already confident that the hypothesis is true, and I don't want to risk nerve damage. Nevertheless, the conclusion drawn is that tightening of the band causes a sensation of numbness.

But let's think about it the other way. Mental events can cause physical events, at least to an interactionalist dualist. I could think to myself, 'in two seconds I will touch my left pinky to my left thumb', wait two seconds without changing my mind, then touch my left pinky to my left thumb. The hypothesis here is that my thoughts caused or at least contributed to my fingers snapping. Although the mechanism of thoughts is unknown and possibly unknowable, the mechanism of the somatic nervous system is better understood. In short, I believe your brain sends acetylocholine down the spinal column and ulnar nerve to the hands where it depolarizes the muscle cell membrane, which releases calcium into the cytosol, which feeds the cross-bridge muscle contraction cycle and ultimately causes the pinky finger to touch the thumb.
SPOILER:
A nerve signal, or rather multiple signals, originate in the upper motor neurons of the primary motor cortex, which release acetylcholine into the synapse between the upper motor neuron and the first alpha motor neuron of a long chain of alpha motor neurons. This chain relays the signal (acetylcholine), out the brain stem, down the spinal cord, along the ulnar nerve, and to the various neuromuscular junctions in the hand - the small space between a nerve ending and muscle cell. The muscle cell contains nicotinic acetylocholine receptors at this junction. When two molecules of acetylocholine bind to those receptors, the receptor opens a non-selective cation channels. The subsequent rush of sodium cations coming in quickly depolarizes the muscle cell's plasma membrane. Some potassium cations trickle out but not enough to balance out the sodium influx. Once the membrane is depolarized, slow-acting voltage-gated potassium ion channels across the cell membrane start letting out potassium, which activate fast-acting voltage-gated sodium ion channels. Within the space of a few microseconds, the muscle cell's membrane is depolarized, repolarized, hyperpolarized (the potassium channels take time to close, too), then repolarized again. This quick fluctuation in voltage spreads across the cell membrane at about 5 meters per second, and activate voltage-dependent dihydropyridine receptors in the muscle's transverse tubules (extensions of the cell membrane that reach inside the cell). These open calcium selective cation channels, and are mechanically linked to ryanodine receptors on the attached sarcoplasmic reticulum, which is basically a calcium repository. Calcium cations flow from the sarcoplasmic reticulum into the cytosol.

Now, skeletal muscle cells each contain what looks like a bundle of smooth red licorice sticks called myofibrils. Each myofibril is divided along its length into many equal segments called sarcomeres. Each sarcomere is made of thick myosin filaments and thin filaments (actin, tropomyosin, and troponin), and they are arranged in a pattern so that the thin filaments form a cup shape on the left and right sides of the thick filament, sort of like your hands holding each end of a pen. Calcium ions in the cytosol bind to troponin proteins on the thin filaments, and the troponin changes shape, causing adjacent tropomyosin proteins to unblock myosin-binding sites on the actin protein. These bind to hook-shaped myocin proteins in the adjacent myocin filament. When the myocin binds to actin, it releases inorganic phosphate, which causes the myocin to "pull" against the actin in what is called a power stroke. The sarcomere shortens about 10nm. Then ADP is released and the myocin remains bound to actin (a cross-bridge) until another ATP molecule from the cytosol binds to the myocin. At that point, the myocin head detaches from the actin site (the recovery stroke) and hydrolizes ATP into ADP and inorganic phosphate, and waits until another myocin-binding site becomes available. This cross-bridge process occurs on both ends of each sarcomere in each myofibril due to the increased calcium concentration, thus causing the muscles in my palm controlling my pinky finger to contract.


What I can't say is that, based on observation, thoughts are always caused by physical events. Certainly physical events can cause sensations, as demonstrated by the wristwatch band giving me a sensation of numbness in my pinky finger. Certainly thoughts can cause or influence physical events, as demonstrated when I thought to touch my pinky and thumb together, then did so. I cannot say with certainly that thoughts are caused by sensations, because the mechanisms of the non-material mind are unobservable and possibly not causal. I cannot observe that tightening my wristwatch band necessarily causes me to touch my thumb and pinky finger together, although there is a logical reason for me to do so (to test whether my finger is numb). If you were to ask me why I picked my thumb instead of the table-top or some other object, I would not necessarily have an answer and might resort to post-hoc justification, or just say it was the first thing that came to my mind. But what process, if any, determined what came to my mind? It is certainly not wildly random, but I could not say whether or not my thoughts are a little random, with consequence.

It may be that there is a physical explanation, but the current state of science does not come close to explaining the physiology of an individual thought. Indeed, science often works on the assumption that there is a physical explanation, and not a stochastic one unless we work in the correspondence principle. If you are unwilling to make the basic assumption of physicalism, I don't think you can conclude that all mental states flow from causes.

Quote:
Originally Posted by begbert2 View Post
You misunderstand - I merely am stating that if the mind is being influenced by randomity (which is possible), that the mind isn't allowing randomity to influence it randomly (so to speak). Any randomity that is influencing the mind is extremely limited in the effects it has on the mental state, to the point that it would be more accurate to say that mind is using the randomity in the way a computer program might use a random number generator,
I agree with all of this.

Quote:
Originally Posted by begbert2 View Post
and only to determine cases where its determinations are so close to being a tie that random perturbations are the only difference between one choice being ahead and the other.
I don't agree with this at all and have no idea how you got came to this conclusion. Random is not the same as equiprobable.

Quote:
Originally Posted by begbert2 View Post
Again, this conclusion is based on observation of behavior - we know randomity is not a major part of human cognition because minds don't act random.
I might agree with you, if we define cognition as the physical behavior caused by the mind. But then all you've done is make a tautology. I had a different definition of cognition in mind, I won't bother trying to make a good written definition but I would want "cognition" to include pure thinking, even the parts that are normally private and unobservable to others.

Quote:
Originally Posted by begbert2 View Post
Or put another way, we know the mind doesn't use many random inputs because there aren't random outputs.

...

Except, as you said, they can't be, not to any significant degree, because mental states observably doesn't fluctuate randomly. There could be a trivial amount of randomity being accessed to break exact ties, but the massive, massive bulk of cognition cannot possibly be based on randomity.
That's not what I said. Are you familiar with the pigeonhole principle? The output of a surjective function says nothing about the domain of its input. I concurred with your statement that brains are in a sense limited by their prior states, that the past matters, and that is still the extent of my agreement.

Quote:
Originally Posted by begbert2 View Post
You're affirming the consequent here (a fallacy). I actually make no such limiting assumption.
I didn't quote the rest of the paragraph, but maybe I should have.
Quote:
Originally Posted by begbert2 View Post
If choices are based on what you know, feel, and want, then they are based on your mental state - which is not random and at any and every given instant is fixed (regardless of model). If they are based on something that's not what you know, feel, or want, like randomity or control signals from an outside god or something, is that free will?
The implication is that "something that's not what you know, feel, or want, like randomity or control signals from an outside god or something" is different from "your mental state". Otherwise your rhetorical question seems out of place. Maybe you are right and I am reading too much into your post.

Quote:
Originally Posted by begbert2 View Post
I totally did establish that the mental state is nonrandom, based on observation of how it behaves combined with your statement "It does not follow that random inputs will lead to nonrandom outputs". Brain state observably doesn't fluctuate randomly, so clearly randomity is not a consequential factor in its function.
We haven't established that all mental states have nonrandom causes, nor that random causes lead to random outcomes, so how can you say the mental state is nonrandom a priori?

Regarding the observations you allude to, what observations? My allegory of the pinky in this post basically says I don't always know why I think one way or another. Just a few sentences prior, you wrote "it would be more accurate to say that mind is using the randomity ... to determine cases where its determinations are so close to being a tie that random perturbations are the only difference between one choice being ahead and the other". I don't agree with that statement and it sounds like you don't agree, either.

Quote:
Originally Posted by begbert2 View Post
In any given instant the brain state must be constant, because it's a single instant. Even something that is fluctuating completely randomly will have a fixed state at each single instant. This part is actually axiomatically true - to say otherwise is to say that there's no such thing as a brain state. (Material or not.)
You are mixing up "brain state" and "mental state" again, but without making any further assumptions I believe your statement does not follow either way. A brain state in a single instant might really be described with a wave function. If you subscribe to a hidden variable theory that's fine, but it is another assumption to add to the list.

With a mental state, the rules are off - you can't rule out the possibility of a nonmaterial "perturbation" affecting the mental state, and you can't really pinpoint which instant such a thing occurred.

Quote:
Originally Posted by begbert2 View Post
YES! That's exactly my point! I'm arguing that by observation of how minds work at an external level we can conclude with certainty that libertarian free will is nonsense. That's exactly what I'm arguing.
I have yet to be convinced, but it's been an interesting debate so far.

Quote:
Originally Posted by begbert2 View Post
So-called libertarian free will is the argument that our choices are made in defiance of our mental state. It argues that the important part of our choices is the part that's made for no reason whatsoever - if you are eating strawberries because you like strawberries the libertarian argument says that that's not you eating them of your own free will. Only if you spastically flail about and randomly shove the strawberries in your mouth is that a freely-made decision.
Conversely, libertarians might assume your mind is influenced but not determined by physical actions. They would deny that every change in mental state flows from a cause. As I understand it, libertarianism empowers the mind with the godly power of being a prime cause. The mind is free to make a choice without any physical reason at all, even in contradiction to logic built on physical evidence; but this is unlikely, because physical things are influential.

Also, to like strawberries is a mental preference, and we could say "it caused you to eat strawberries", but the Libertarian would say this is only a manner of speaking. The consumption of strawberries was only by the grace of the mind which had the power to reject both logic and the strawberries, and could have effected an alternate reality where strawberries were not eaten. It does not follow that the decision to eat strawberries is made without free will just because it makes sense.

Neither must the mind always have free will; I doubt any libertarian would deny that some of the time, the mind is unable to physically effect its decisions; and I'm sure some libertarians consume mind-altering drugs for the express purposes of forcibly altering the mind. Libertarianism is not necessarily incompatible with the concept of a mental disease restricting free will, either.

Quote:
Originally Posted by begbert2 View Post
And libertarian free will doesn't presuppose magic - that's what nonmaterialism offers, but libertarian free will doesn't have anything to do with nonmaterialism.
If by magic you mean antimaterialism, I disagree and assert that libertarianism does require antimaterialism. Libertarianism and antimaterialism are not the same, but it's like the rectangle and the square: libertarianism is a form of antimaterialism.

Quote:
Originally Posted by begbert2 View Post
I am totally cool with compatiblism, not because I assumed the conclusion, but because observation of mental behavior reveals that minds work in a way that is compatible with hard determinism.
When I said "hard determinism", I actually meant the view that determinism is true and incompatible with free will. Hard determinism is mutually exclusive with compatibilism by definition. But I agree with you that hard determinists and compatibilists are using different words to describe the same thing. There is no real debate to be had between philosophers of those two groups.

~Max