On Fri, Feb 4, 2011 at 12:05 PM, Colin Hales <[email protected]> wrote:
> > Can the behaviour of the neurons including the electric fields be > > simulated? For example, is it possible to model what will happen in > > the brain (and what output will ultimately go to the muscles via > > peripheral nerves) if a particular sequence of photons hits the > > retina? If that is a theoretical impossibility then where exactly is > > the non-computable physics, and what evidence do you have that it is > > non-computable? > Lots of aspects to your questions.... and I'll try and answer Bruno at the > same time. > > 1) I am in the process of upgrading neural modelling to include the fields > in the traditional sense of simulation of the fields. The way to think of it > is that the little capacitor in the Hodgkin-Huxley equilvalent circuit is > about to get a whole new role. Great! That is another step towards simulating brains. > 2) Having done that, one can do simulations of single unit, multiple unit, > populations etc etc...You may be able to extract something verifiable in the > wet-lab. > > 3) However, I would hold that no matter how comprehensive the models, no > matter how many neurons ... even the whole brain and the peripheral > nerves...they will NOT behave like the real thing in the sense that such a > brain model cannot ever 'be' a mind. The reason is that we 'BE' the fields. > We do not 'BE' a description of the fields. The information delivered by > 'BE'ing the field acts in addition to that described by the > 3rd-person-validated system of classical partial differential equations that > are Maxwell's equations. I understand that this is your position but I would like you to consider a poor, dumb engineer who neither knows nor cares about philosophy of mind. All he cares about is making an accurate model which will predict the pattern of motor neuron firings for a human brain given a certain initial state. Doing this is equivalent to constructing a human level AI, since the simulation could be given information and would respond just as a human would given the same information. Now, I take it that you don't believe that such predictions can be made using a mathematical model. Is that right? > 4) A given set of photons, can result from an infinity of different > configurations of the distal world. A single red photon can come across the > room from your xmas decorations or across the galaxy from a supernova. It is > a fundamentally degenerate relationship. Yet the brain inherits enough > information to converge on a visual scene that captures the difference. HOW? > I think I know, but that explanation is too long and doesn't matter. The > fact is that the EM fields deliver _extra_ information inherited from their > relationship with space itself. It has to. There's no place else or it to > come from! I don't think it's possible to work out where a photon comes from except in context. Regardless, we can bypass the complexities of perception by discussing only information imparted by written communication. > 5) Regardless of my wacky ideas about space, I'd like to reinforce the > implications of the particular case of the scientist, who is trying to find > out about the distal natural world from position of fundamental ignorance. > If you claim that we have enough information to overcome the degeneracy, > then you already have what the scientist wants...knowledge of the unknown > external distal world....so you are not actually doing science. You already > know. This is the killer logical position. If you say a computer can do it, > you are saying, in effect, that science does nothing/already knows > everything. Science makes hypotheses and tests them for internal consistency and against empirically obtained data. Why couldn't a computer do the same? > ============ > > In the end, then, I am not saying that there is something uncomputable in > the sense that it is impossible to 'simulate' it. You can simulate anything! > What I am saying is that if you could _you wouldn't bother_ because you'd > already know everything. To accurately simulate a scientist you have to > simulate (a) the scientist and (b) the entire environment of the scientist, > when the scientist is trying to uncover the unknown and you can't simulate > it because you don;t know it. I use the scientist as a model for the > generally intelligent behaviour. I don't understand what problem you have with information provided to the simulated scientist by instruments connected to the computer or even written data compiled by another scientist. -- 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 protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/everything-list?hl=en.
