On Fri, Oct 28, 2011 at 6:13 AM, Craig Weinberg <whatsons...@gmail.com> wrote:
> Let's say that I watch a football game on TV and describe what I see. > Is there now a direct connection between my larynx and a football > field somewhere? What is this connection made of? Is this the kind of > purely semantic-philosophical 'connection' you are talking about being > what connects the retina and larynx? There is a causal connection between your larynx and the football field, since what happens on the football field affects your larynx. If it did not, you could not describe what happened on the football field. You cannot describe a football game if the light from it has not reached you, for example, since information cannot get to you faster than light. >> How does "the necessity of neurons to respond to their environment" go >> against determinism? > > Because living cells must confront unanticipated and novel > circumstances in their environment which cannot be determined, nor can > the responses be determined in advance. Inorganic molecules don't care > if they survive or not so their interactions are more deterministic > and passive. The environment can provide a rich variety of inputs to an entity but that does not mean that the entity must be programmed to respond differently to every input. For example, a neuron may see see a concentration of dopamine molecules that varies over a trillionfold range, but it has only two responses: depolarise its membrane if the concentration is above a certain threshold, don't if it isn't. The neuron does not know what the dopamine concentration is going to be ahead of time, but it looks at what it is and responds according to this algorithm. >> I think this is again a very basic >> misunderstanding that you have. A lighting circuit behaves completely >> deterministically, ON when the switch is down and OFF when the switch >> is up. The circuit doesn't know when someone is going to come along >> and flick the switch, but modelling the circuit does not involve >> modelling the entire universe. > > No, it's a very basic misunderstanding that you have that a living > organism is the same thing as a light switch. Does a lighting circuit have to be programmed to know exactly when someone is going to walk into the room in a year's time and flick the switch? That's the sort of requirement you seem to have for a model of a neuron. >> If the components are deterministic then the system is deterministic, >> although it may show complex, surprising or chaotic behaviour. > > That would make sense if we were still in the 19th century. In the > last 150 years a lot has changed though. Heisenberg? Goedel? This is > not some fringe idea that I came up with. > > "We have seen that extremely simple dynamical > systems can behave in ways very much at odds with our > intuition about the deterministic nature of classical > physics," - http://www.jhuapl.edu/techdigest/td/td1604/Sommerer.pdf There are two considerations here. One is classical chaotic, or non-linear, systems. These are deterministic but unpredictable. The brain is probably such a system. The other consideration is true randomness, which occurs in quantum level systems. Radioactive decay is an example of this. (Actually, quantum mechanics is still deterministic under the Many Worlds Interpretation, but it is truly random from the point of view of any observer since they cannot know which world they will end up in). Truly random systems can still be very predictable: we can be pretty sure how much of a radioisotope will decay after a certain time. >> Everything is ultimately just a dumb conduit. It's the combination of >> many dumb conduits that makes you smart. > > Interesting double standard. You say that deterministic components > cannot scale up to anything except deterministic wholes, yet you also > say that many dumb conduits make you smart. To me it's clearly the > opposite. Dumb conduits make nothing but dumb conduits. A quadrillion > ping pong balls can make... nothing but ping pong balls. This means to > me that atoms are smarter than ideal spheres, and that intelligence > scales up into more complex, indeterminate intelligence. It's the complexity of interacting components that scales up to intelligence. >> The visual cortex has projections to the temporal and parietal lobes >> but you don't need to know the details to know that there *must* be a >> connection if a person can describe what they see. > > No. There is no connection, unless you are talking about a > philosophical connection. There is no direct transfer of > electrochemical signalling between the visual cortex and the larynx > which bypasses the brain. Of course it doesn't bypass the brain - the connection consists of the neural connections in the brain. >> The depolarisation of neurons occurs deterministically, and the result >> of that is that you decide to move your arm. > > Depolarization occurs deterministically or voluntarily, depending on > the situation. It is false that depolarization results in the decision > to move your arm. Depolarization would result in a reflex muscle > contraction where you do *not* decide to move your arm. If I decide to > move my arm, the experience of that decision *is* the depolarization > of the region of the brain associated with that voluntary process (not > the involuntary process). > >> If it were the other way >> around it would appear as magic. > > You keep saying it would appear as magic, but it appears only as > ordinary voluntary movement. > >> Indeed, there are the famous >> experiments of Benjamin Libet which showed that first you move your >> arm, then decide to move your arm. In other words, free will may not >> even be concurrent with action, but rather follow retrospectively. > > The observations of those experiments are that subjects responding to > repeating stimulus show brain activity indicating which response they > will choose well before they report that they are deciding to make > that decision. The interpretation that the brain activity precedes the > decision is premature, and even they do not go so far as to suggest > that conclusion. Such an obviously nonsensical conclusion would be a > last resort when all other possibilities have been exhausted. > > I think that all the experiment shows is that human consciousness is > not a monolithic entity, but rather an awareness of awarenesses. There > is nothing to say that the very earliest activity in the brain is not > a sentient decision making event. There is also nothing to say that > the subject is not anticipating the routine of responding to repeated > calls to choose. If I was sitting in a chair choosing A or B over and > over, I would pick up on the pattern and begin to subconsciously > anticipate my next choice, probably even before the next stimulus. > > At best the experiment shows that it takes a while for the free will > of the 'sub-selves' which make up our conscious awareness to be > reflected in other areas of the brain which know that they know that > they have made a decision and still longer for the reporting/ > acknowledgement process to be initiated. Even if the experiments have been misinterpreted, the fact remains that free will *could* work that way. There is nothing in our experience which suggests that it could not. >> Where does this description of the mechanism of quorum sensing in >> bacteria from Wikipedia go wrong in your view: >> >> "Bacteria that use quorum sensing constantly produce and secrete >> certain signaling molecules (called autoinducers or pheromones). These >> bacteria also have a receptor that can specifically detect the >> signaling molecule (inducer). When the inducer binds the receptor, it >> activates transcription of certain genes, including those for inducer >> synthesis. There is a low likelihood of a bacterium detecting its own >> secreted inducer. Thus, in order for gene transcription to be >> activated, the cell must encounter signaling molecules secreted by >> other cells in its environment. When only a few other bacteria of the >> same kind are in the vicinity, diffusion reduces the concentration of >> the inducer in the surrounding medium to almost zero, so the bacteria >> produce little inducer. However, as the population grows, the >> concentration of the inducer passes a threshold, causing more inducer >> to be synthesized. This forms a positive feedback loop, and the >> receptor becomes fully activated. Activation of the receptor induces >> the up-regulation of other specific genes, causing all of the cells to >> begin transcription at approximately the same time. This coordinated >> behavior of bacterial cells can be useful in a variety of situations. >> For instance, the bioluminescent luciferase produced by V. fischeri >> would not be visible if it were produced by a single cell. By using >> quorum sensing to limit the production of luciferase to situations >> when cell populations are large, V. fischeri cells are able to avoid >> wasting energy on the production of useless product." >> > > It seems ok to me as a third person description: > > "These bacteria also have a receptor that can specifically detect the > signaling molecule (inducer)." > > Sense. The bacteria secrete an 'odor' let's say. They can tell the > difference between their own odor and others, they can tell how > intense the odor is, and they know that when the odor gets intense > enough, then something is going to happen. > > "Activation of the receptor induces the up-regulation of other > specific genes, causing all of the cells to begin transcription at > approximately the same time. This coordinated behavior of bacterial > cells can be useful in a variety of situations." > > Motive. When the conditions are right, all of the cells feel it and > begin modifying their own genetic transcription together as a group. These are all mechanistic processes which can be easily modelled computationally. If you don't agree then what sort of behaviour would count as mechanistic from bacteria? >> If high level non-computable, non-deterministic, non-physical >> processes act on matter then as I have said many times there should be >> direct laboratory evidence of this > > There is. If you tell someone to imagine playing tennis, they can > induce specific behaviors in the brain if they choose to comply. Which is consistent with standard neuroscience theories, or they would have been dropped long ago. >> , such as a neuron depolarising its >> membrane contrary to the well-understood and deterministic factors >> known to be behind depolarisation. > > You keep going back to this caricature of biology. There are ranges of > conditions within which depolarization can take place, but those > conditions are met with proper nutrition and comfortable operating > environment. Spontaneous neural activity is spontaneous > depolarization. There is no well-understood deterministic factor > involved, and more than an analysis of traffic can be reduced to > deterministic factors of traffic signals. No, voluntary choice does > not mean the cars are going against the light, it just means that the > voluntary choices are the lights themselves. You cannot deny that > neurons (and other cells and organisms) respond to their environment. > How does the environment cause changes to the well-understood and > deterministic factors that cite? How does a picture of a bunny rabbit > change polarization factors in the brain, but deciding to move your > arm does not? Just where do you get the idea that "spontaneous neural activity" means spontaneous depolarisation? I have tried to explain several times how depolarisation occurs and your answer on one occasion was that you can read Wikipedia as well. Apparently, you cannot understand a basic account of how neurons work, or you would not make these statements. >> If neurons always follow physical >> laws then they only behave deterministically, and hence the whole >> brain behaves deterministically, even if chaotically and >> unpredictably. > > Logical fallacy. Neurons follow physical laws, but they also follow > biological agendas. Please explain to me how it is that salmon are > able to swim upstream to spawn? Are they magic? Do they defy gravity? > Do the laws of physics change when they spawn? How is it that one > species of fish does something different like that compared to other > fish if they are both made of the same deterministic physical > behaviors? In what way is the salmon's behavior deterministic? Which part of the salmon's behaviour do you not understand? Do you think swimming upstream is impossible without a special vital spark or do you think it would be impossible to program a computer with a motivation to swim upstream? >> If you feel life is pointless because it is the way it is whose fault is >> that? > > Who said anything about life being pointless? Life has countless > meanings. Why won't you answer my question though? You claim that > everything is either determined or random. So I ask you again...are > your responses to this comment determined or are they random? For what it's worth I think that quantum level events in the brain add a degree of randomness to what is otherwise a deterministic process. To what extent the randomness is important is not clear. >> A scientist will always try to come up with hypotheses which he tests >> by experiment. Have you ever studied science at University level or >> spent any time with scientists? > > Sure I have. Psychology, Anthropology, Biology, Physics. I took a > class called Human Consciousness once actually. Actually I am > collaborating with a neuroscientist currently. His specialty is > perception and he seems quite supportive of my ideas. We are > definitely on the same page as far as perception is concerned. > > How about you? Have you studied biology, neurology, psychology, and > consciousness in college? I have a medical degree and I have done some basic research in cell biology and molecular biology, though that was long ago. Currently I only do clinical work. -- Stathis Papaioannou -- You received this message because you are subscribed to the Google Groups "Everything List" group. To post to this group, send email to email@example.com. To unsubscribe from this group, send email to everything-list+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/everything-list?hl=en.