On 8 June 2015 at 11:14, meekerdb <[email protected]> wrote: > On 6/7/2015 3:00 PM, LizR wrote: > > On 8 June 2015 at 05:08, Bruno Marchal <[email protected]> wrote: > >> >> On 07 Jun 2015, at 18:35, John Clark wrote: >> >> On Sat, Jun 6, 2015 Bruno Marchal <[email protected]> wrote: >> >> >> An event is just a place and a time; are you saying that >>>> mathematics is incapable of handling 4 coordinates? >>> >>> >>> > Of course, applied mathematics exists, and you can represent event >>> in mathematics, but you shopuld not confuse something (a physical event) >>> and its mathematical representation. >>> >> >> I am not confusing that but I think sometimes you might be confusing a >> physical thing with the language (mathematics) the descriptive >> representation of the thing is presented in. Or maybe not, maybe you're >> right and mathematics is more than just a language and is more fundamental >> than physics; nobody knows including you. >> >> Nobody can know. But we can reason from hypothesis. With the >> computationalist hypothesis, the immateriality of consciousness is >> contagious on the possible environment. Nobody pretends this is obvious, >> especially for people stuck at the step 3. >> >> The question being asked is, why hypothesis best explains > consciousness? Comp attempts to take the default materialist assumption, > that consciousness is a (very, very complicated) form of computation, and > to derive results from that assumption. > > Hence what I've called comp1 is the default materialist hypothesis (also > known as the strong AI thesis, I think) - this is more or less equivalent > to the idea that a computer could, given a suitable programme and > resources, be conscious. From this Bruno attempts to show, via a chain of > reasoning, that the computations involved have to take place in > arithmetical reality ("Platonia"). This conclusion I call comp2. The task > of anyone who disagrees is simply to show that comp2 doesn't follow from > comp1. > > There are various ways to try to show this. One is to doubt the starting > assumptions ("comp1"). The starting assumptions include the idea that > simple arithmetic exists independently of mathematicians - that 2+2=4 was > true in the big bang, for example. > > > I think that assumes that "true" and "exist" are the same thing. One can > affirm that Watson was Holmes assistant without admitting that either one > existed. So while everyone agrees that 2+2=4 by definition, it's not so > clear that arithmetic objects exist. > > Yes, of course it isn't clear. But 2+2=4 isn't "by definition" it's the result of empirical observation of - as John wuold say - material objects.
> The universe appears to obey certain bits of methematics to high > precision, or alternatively you could say that various bits of maths appear > to correctly describe the behaviour of the universe and its constituents to > high precision. So that is the "which comes first?" question, which as you > correctly say we can't know (indeed we can't know anything, if "know" means > justified true belief, apart from the fact that we are conscious, as > Descartes mentioned). > > > Note that Bruno rejects the conditioning on "justified". Plato's > Theaetetus dialogue defines "knowledge" as "true belief". I think that's > a deficiency in modal logic insofar as it's supposed to formalize good > informal reasoning. But I can see why it's done; it's difficult if not > impossible to give formal definition of "justified". > > Yes. > So one can doubt comp1 by doubting either that consciousness is a > computation, or that maths exists independently of mathematicians. > > Then one can doubt the steps of the argument. I personally find little > to doubt, assuming comp1, until we reach step 7 or 8, or whichever step is > the MGA. (There has been a lot of heat about pronouns, but as far as I can > see this hasn't made a dent in the arguments presented.) > > So the other main point of attack is at the comp2 end, so to speak, with > the MGA. There is Brent's "light cone" argument, which IMHO seems > unconvincing because one can make a "cut" between a brain and the world > along the sensory nerves - this is basically saying that a person could be > a brain in a vat, and never know it. But it also fails if one can in theory > have an AI, because an AI is by hyopthesis a digital machine and could > therefore could be re-run and given the same inputs, and due to the nature > of computation would have to repeat the same conscious experiences. > > > Both of those scenarios assume that there was an external world with which > the brain/AI was related to in the past and which provides meaning to the > computational processes that are *ex hypothesi* now isolated from the > world. The relation need not even be direct, i.e. the AI was constructed > by a programmer whose knowledge of the world provides the meaning. But > without some such relation it's hard to say that the computational > processes are *about* anything, that they are not just noise. > Yes, that's the problem in a nutshell - why aren't conscious computations just noise? (Or are they?) > And then that description falls foul of Bruno/Maudlin's argument about > leeching away the material support for the computation until it is turned > into a replayed recording. At this point we can use "Russell's paradox" - > sorry, I mean argument - that a recording of such complexity may indeed be > conscious. The MGA seems to hand-wave a bit about this whole process - like > the Chinese room, we "simply" record the activities of the processing > devices and then "simply' project the movie onto the system, and so on, > leaving aside the Vast size of the envisaged apparatus. Nevertheless, if we > assume comp1 then we assume by hypothesis that a recording isn't conscious > (only a computation can be conscious, according to comp1). So that's really > a comp1 objection. > > > A good point. I think comp1 is not very well defined and that leads to > the ambiguity in the MGA. The intuition is that consciousness is due to > some special kind of activity of the brain. It must be some kind of > information processing and that implies it can at least be approximated by > digital computer. But to say it *is* computation, ala Turing, is really > going a little further: It's assuming that the relation to the afferent and > efferent nerves can be abstracted as well as the brain processes, and in > fact this abstraction is, I think, contagious and it implies abstracted > bodily processes, physical interaction of the body with the environment, > the environment with the universe,... Or taking the contagion the other > way, it implies that the physical existence of the computation was an > essential part - even though "physical existence" is not locally defined > and is only relative, holistic concept. > Yes. I have to go now but will look at this later. > > Brent > > > So the question in the end is which is the most reasonable hypothesis. > How does materialism explain consciousness? How does comp explain the > appearance of a material universe? > > Over to you. > -- > You received this message because you are subscribed to the Google Groups > "Everything List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/everything-list. > For more options, visit https://groups.google.com/d/optout. > > > -- > You received this message because you are subscribed to the Google Groups > "Everything List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/everything-list. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Everything List" group. 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