3 reply to Roddus' comment
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Edit (reply to Roddus' comment below)... Firstly, for concreteness, let's please do away with this unnecessarily vague "voltage level" terminology, which you've used here and in preceding comments above. See, e.g., https://en.wikipedia.org/wiki/Bit#Physical_representation for the correspondence between bits and voltage levels. We're talking about Searle's "symbols" (sequences of bits), regardless of their physical representation, which simply happens to be voltage levels in electronic digital computers.

Regarding "meaning", with respect to computers, I'd guess what you might want to study could be "denotational semantics" (e.g., https://en.wikipedia.org/wiki/Denotational_semantics and many other google hits) and "domain theory" (e.g., https://en.wikipedia.org/wiki/Domain_theory ). Then it's the so-called "semantic function", which maps syntax (the denotation represented by strings of symbols) to semantics (the syntax's meaning represented in a so-called Scott domain), that captures the mathematical idea of "meaning" as it pertains to computability. The short paper https://www.cs.colorado.edu/~bec/courses/csci5535/reading/densem.pdf seems like a pretty good intro to me (I'm not googling any wikipedia-type stuff that comes anywhere near adequate). A longer-but-more-comprehensive intro is (seems to me) http://homepage.divms.uiowa.edu/~slonnegr/plf/Book/Chapter9.pdf And/or try googling "semantic function" denotational (put "semantic function" in quotes as shown, followed by denotational) for additional tutorial papers.

As for Searle and his Chinese Room conclusions, you'd need to compare and contrast "meaning" with respect to computers, versus "meaning" with respect to consciousness. But only the former is well-enough-defined for any rigorous comparison. And if you're really interested, I think you might need to further study domains, maybe particularly the idea of approximation as represented by their poset ordering, whereby "meaning" can start out vague and become better-and-better defined with more-and-more syntax. But that would involve a pretty significant effort, far afield from any direct relation to "consciousness". So I wouldn't recommend it unless you're really, really interested.

The theoretical computer science aspects might (again judging from your profile) be adequately interesting, but maybe not the related-to-consciousness aspects... Are computers (i.e., can computers simulate) "conscious"? Or can they exhibit behaviour indistinguishable from consciousness? Searle apparently says "no". Whether or not his argument's conclusive is maybe debatable, but his definition of "computer" is entirely adequate. Any further argument would have to discuss the ultimate capabilities of "symbol manipulation" -- just how far can that take you? And that's indeed somewhat of an open question. It's closed with respect to computable function theory, but meaning/semantics/etc not equally well closed.

Edit (reply to Roddus' comment below)... Firstly, for concreteness, let's please do away with this unnecessarily vague "voltage level" terminology, which you've used here and in preceding comments above. See, e.g., https://en.wikipedia.org/wiki/Bit#Physical_representation for the correspondence between bits and voltage levels. We're talking about Searle's "symbols" (sequences of bits), regardless of their physical representation, which simply happens to be voltage levels in electronic digital computers.

Regarding "meaning", with respect to computers, I'd guess what you might want to study could be "denotational semantics" (e.g., https://en.wikipedia.org/wiki/Denotational_semantics and many other google hits) and "domain theory" (e.g., https://en.wikipedia.org/wiki/Domain_theory ). Then it's the so-called "semantic function", which maps syntax (the denotation represented by strings of symbols) to semantics (the syntax's meaning represented in a so-called Scott domain), that captures the mathematical idea of "meaning" as it pertains to computability. The short paper https://www.cs.colorado.edu/~bec/courses/csci5535/reading/densem.pdf seems like a pretty good intro to me (I'm not googling any wikipedia-type stuff that comes anywhere near adequate). A longer-but-more-comprehensive intro is (seems to me) http://homepage.divms.uiowa.edu/~slonnegr/plf/Book/Chapter9.pdf And/or try googling "semantic function" denotational (put "semantic function" in quotes as shown, followed by denotational) for additional tutorial papers.

As for Searle and his Chinese Room conclusions, you'd need to compare and contrast "meaning" with respect to computers, versus "meaning" with respect to consciousness. But only the former is well-enough-defined for any rigorous comparison. And if you're really interested, I think you might need to further study domains, maybe particularly the idea of approximation as represented by their poset ordering, whereby "meaning" can start out vague and become better-and-better defined with more-and-more syntax. But that would involve a pretty significant effort, far afield from any direct relation to "consciousness". So I wouldn't recommend it unless you're really, really interested.

The theoretical computer science aspects might (again judging from your profile) be adequately interesting, but maybe not the related-to-consciousness aspects... Are computers (i.e., can computers simulate) "conscious"? Or can they exhibit behaviour indistinguishable from consciousness? Searle apparently says "no". Whether or not his argument's conclusive is maybe debatable, but his definition of "computer" is entirely adequate. Any further argument would have to discuss the ultimate capabilities of "symbol manipulation" -- just how far can that take you? And that's indeed somewhat of an open question. It's closed with respect to computable function theory, but meaning/semantics/etc not equally well closed.

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Yes, he (correctly) means "a formal-symbol manipulating device". But "manipulation" needs a little clarification. The usual textbook formalism is given by the lambda calculus, e.g., https://en.wikipedia.org/wiki/Lambda_calculus#Formal_definition (google "lambda calculus" for lots more).

But electronic devices natively implement only a much simpler (architecture-dependent) machine language, something typically more-or-less like Knuth's MIX, e.g., https://en.wikipedia.org/wiki/MIX (google "Knuth MIX").

However, a lambda-calculus-interpreter can always be written in any such machine language. Indeed, "Church's Thesis" and "Turing Completeness" (more terms for you to google) guarantee that just about any sensible formal idea of "manipulation" is ultimately equivalent to all others.

That is, there's a class of so-called "computable functions" (google that), meaning that a sequence of symbols representing input (the function's argument) can be manipulated into another sequence representing output (the function's value). If no such manipulations exist, the function's not computable (google "halting function" for a non-computable example). And all computer languages, i.e., all formal ideas of "manipulation", can ultimately calculate exactly the same class of computable functions.

So Searle's ultimately and equivalently saying that consciousness isn't (can't be simulated by) computable functions. But your comment, "...defining a computer as a symbol-manipulating device just seems to add fog to the AI landscape", seems to conflate AI with consciousness. AI, aka "expert systems", are certainly computable, but certainly not consciousness. And nobody ever claims any such thing. I think maybe your question arises from a misunderstanding about that.

Edit... Hmm, now taking a look at your profile, I wouldn't imagine you'd have any confusion/misunderstanding about that. But then I don't see how you'd have any question about Searle's remark whatsoever. So what's your question, more exactly?

Yes, he (correctly) means "a formal-symbol manipulating device". But "manipulation" needs a little clarification. The usual textbook formalism is given by the lambda calculus, e.g., https://en.wikipedia.org/wiki/Lambda_calculus#Formal_definition (google "lambda calculus" for lots more).

But electronic devices natively implement only a much simpler (architecture-dependent) machine language, something typically more-or-less like Knuth's MIX, e.g., https://en.wikipedia.org/wiki/MIX (google "Knuth MIX").

However, a lambda-calculus-interpreter can always be written in any such machine language. Indeed, "Church's Thesis" and "Turing Completeness" (more terms for you to google) guarantee that just about any sensible formal idea of "manipulation" is ultimately equivalent to all others.

That is, there's a class of so-called "computable functions" (google that), meaning that a sequence of symbols representing input (the function's argument) can be manipulated into another sequence representing output (the function's value). If no such manipulations exist, the function's not computable (google "halting function" for a non-computable example). And all computer languages, i.e., all formal ideas of "manipulation", can ultimately calculate exactly the same class of computable functions.

So Searle's ultimately and equivalently saying that consciousness isn't (can't be simulated by) computable functions. But your comment, "...defining a computer as a symbol-manipulating device just seems to add fog to the AI landscape", seems to conflate AI with consciousness. AI, aka "expert systems", are certainly computable, but certainly not consciousness. And nobody ever claims any such thing. I think maybe your question arises from a misunderstanding about that.

Yes, he (correctly) means "a formal-symbol manipulating device". But "manipulation" needs a little clarification. The usual textbook formalism is given by the lambda calculus, e.g., https://en.wikipedia.org/wiki/Lambda_calculus#Formal_definition (google "lambda calculus" for lots more).

But electronic devices natively implement only a much simpler (architecture-dependent) machine language, something typically more-or-less like Knuth's MIX, e.g., https://en.wikipedia.org/wiki/MIX (google "Knuth MIX").

However, a lambda-calculus-interpreter can always be written in any such machine language. Indeed, "Church's Thesis" and "Turing Completeness" (more terms for you to google) guarantee that just about any sensible formal idea of "manipulation" is ultimately equivalent to all others.

That is, there's a class of so-called "computable functions" (google that), meaning that a sequence of symbols representing input (the function's argument) can be manipulated into another sequence representing output (the function's value). If no such manipulations exist, the function's not computable (google "halting function" for a non-computable example). And all computer languages, i.e., all formal ideas of "manipulation", can ultimately calculate exactly the same class of computable functions.

So Searle's ultimately and equivalently saying that consciousness isn't (can't be simulated by) computable functions. But your comment, "...defining a computer as a symbol-manipulating device just seems to add fog to the AI landscape", seems to conflate AI with consciousness. AI, aka "expert systems", are certainly computable, but certainly not consciousness. And nobody ever claims any such thing. I think maybe your question arises from a misunderstanding about that.

Edit... Hmm, now taking a look at your profile, I wouldn't imagine you'd have any confusion/misunderstanding about that. But then I don't see how you'd have any question about Searle's remark whatsoever. So what's your question, more exactly?

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Yes, he (correctly) means "a formal-symbol manipulating device". But "manipulation" needs a little clarification. The usual textbook formalism is given by the lambda calculus, e.g., https://en.wikipedia.org/wiki/Lambda_calculus#Formal_definition (google "lambda calculus" for lots more).

But electronic devices natively implement only a much simpler (architecture-dependent) machine language, something typically more-or-less like Knuth's MIX, e.g., https://en.wikipedia.org/wiki/MIX (google "Knuth MIX").

However, a lambda-calculus-interpreter can always be written in any such machine language. Indeed, "Church's Thesis" and "Turing Completeness" (more terms for you to google) guarantee that just about any sensible formal idea of "manipulation" is ultimately equivalent to all others.

That is, there's a class of so-called "computable functions" (google that), meaning that a sequence of symbols representing input (the function's argument) can be manipulated into another sequence representing output (the function's value). If no such manipulations exist, the function's not computable (google "halting function" for a non-computable example). And all computer languages, i.e., all formal ideas of "manipulation", can ultimately calculate exactly the same class of computable functions.

So Searle's ultimately and equivalently saying that consciousness isn't (can't be simulated by) computable functions. But your comment, "...defining a computer as a symbol-manipulating device just seems to add fog to the AI landscape", seems to conflate AI with consciousness. AI, aka "expert systems", are certainly computable, but certainly not consciousness. And nobody ever claims any such thing. I think maybe your question arises from a misunderstanding about that.