The Semantics Differentiation of Minds and Machines

John David Funge writes "In Dr David Ellerman's book Intellectual Trespassing as a Way of Life there are a number of interesting essays. But there is one particular essay, entitled "The Semantics Differentiation of Minds and Machines," that caught my attention and which should be of interest to Slashdot readers. In that essay Dr Ellerman claims that "after several decades of debate, a definitive differentiation between minds and machines seems to be emerging into view." In particular, Dr Ellerman argues that the distinction between minds and machines is that while machines (i.e., computers) make excellent symbol manipulation devices, only minds have the additional capacity to ascribe semantics to symbols." Read the rest of John's review. Intellectual Trespassing as a Way of Life author David P. Ellerman pages 290 pages publisher Rowman & Littlefield Publishers, Inc. rating 7 reviewer John David Funge ISBN 0847679322 summary Dramatic changes or revolutions in a field of science are often made by outsiders or "trespassers".

However, Dr Ellerman's argument appears circular. In particular, Dr Ellerman seems to have decided that, by definition, the only possible semantic interpretation for any collection of wires, capacitors, transistors, etc. that we would commonly refer to as a "computer" is as nothing more than a symbol manipulation device. While a computer is indeed (at the very least) a symbol manipulation device, what is there to prevent another mind ascribing additional semantic interpretations to the collection of wires, capacitors, transistors, etc. that we commonly refer to as a "computer"? In particular, what if my mind were willing to make the semantic interpretation that a computer is a device that can both manipulate symbols and can also ascribe semantics to symbols.

Moreover, what if I one day met a collection of blood vessels, skin, bones, etc. called Dr Ellerman? What would prevent me from ascribing to him the semantic interpretation that he is nothing more than a symbolic manipulation device? After all, Dr Ellerman concedes that their may be no way of distinguishing minds from machines purely on the basis of behavior. That is he specifically acknowledges that computers may one day pass the Turing test. So why would my mind not then be able to legitimately ascribe any semantic interpretation (that fits the observed behavior) I see fit to either humans or machines?

It seems that Dr Ellerman's essay considers two different types of physical devices that are potentially indistinguishable on the basis of behavior. Then arbitrarily defines one type of device (computers) to correspond to nothing more than symbolic manipulation and the other (human brains) to have the additional ability to ascribe semantics. Upon adopting these two axioms, he is then (somewhat unsurprisingly) able to conclude there is a distinction! But the distinction simply arises from the fact that he has arbitrarily defined a distinction in the first place.

In another essay in the collection, entitled "Trespassing against the Happy Consciousness of Orthodox Economics," Dr Ellerman argues that modern Western societies are not as free from slavery as orthodox economics would have us believe. In particular, he concludes that work in non-democratic firms is nothing less than a form of "temporary voluntary slavery". It would be ironic therefore if his essay on minds and machines were one day used to justify the slavery of (non-human) machines. Indeed, Dr Ellerman's characterization of the supposed intrinsic differences between humans and machines is sadly reminiscent of the despicable and unscientific arguments about intrinsic racial differences that were once used to justify human slavery."
You can purchase Intellectual Trespassing as a Way of Life from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.

Comments

semiotics

[gEvil (beta)]

I believe the proper term for this field is semiotics, the study of the assignation of meaning to symbols and signs.

Re:semiotics

[Anonymous Coward]

Semiotics and semantics are not the same thing. Semantics is studied in a variety of fields, including philosophy, linguistics, logic and computer science. Semiotics doesn't seem to be involved here.

I think I've heard this one before...

[Anonymous Coward]

*COUGH*Searle*COUGH

Re: is the brain a digital computer?

[johnrpenner]

this point has been made before,
by cognitive scientist john searle in his paper:

    is the brain a digital computer?

in the summary, searle puts it this way:

--| Summary of the Argument |---

This brief argument has a simple logical structure and I will lay it out:

On the standard textbook definition, computation is defined syntactically in terms of symbol manipulation.

But syntax and symbols are not defined in terms of physics. Though symbol tokens are always physical tokens, "symbol" and "same symbol" are not defined in terms of physical features. Syntax, in short, is not intrinsic to physics.

This has the consequence that computation is not discovered in the physics, it is assigned to it. Certain physical phenomena are assigned or used or programmed or interpreted syntactically. Syntax and symbols are observer relative.

It follows that you could not discover that the brain or anything else was intrinsically a digital computer, although you could assign a computational interpretation to it as you could to anything else. The point is not that the claim "The brain is a digital computer" is false. Rather it does not get up to the level of falsehood. It does not have a clear sense. You will have misunderstood my account if you think that I am arguing that it is simply false that the brain is a digital computer. The question "Is the brain a digital computer?" is as ill defined as the questions "Is it an abacus?", "Is it a book?", or "Is it a set of symbols?", "Is it a set of mathematical formulae?"

Some physical systems facilitate the computational use much better than others. That is why we build, program, and use them. In such cases we are the homunculus in the system interpreting the physics in both syntactical and semantic terms.

But the causal explanations we then give do not cite causal properties different from the physics of the implementation and the intentionality of the homunculus.

The standard, though tacit, way out of this is to commit the homunculus fallacy. The humunculus fallacy is endemic to computational models of cognition and cannot be removed by the standard recursive decomposition arguments. They are addressed to a different question.

We cannot avoid the foregoing results by supposing that the brain is doing "information processing". The brain, as far as its intrinsic operations are concerned, does no information processing. It is a specific biological organ and its specific neurobiological processes cause specific forms of intentionality. In the brain, intrinsically, there are neurobiological processes and sometimes they cause consciousness. But that is the end of the story.\**

--

regards,
j.

One of many examples.

[jd]

Humans are excellent at differentiating between things that are really the same, or inventing totally new layers of reality because of flawed assumptions about the way the world works. Today, I think we've gone beyond needing to think of fire, earth, air and water as being the four elements from which all physical matter is constructed, and light does not need an aether to "travel through".

For that reason, any attempt to differentiate the mind and computers by using comparisons that aren't really meaningful or applicable should be thrown out. Maybe computer-based intelligence will never exist, but if that is the case, it won't be for the reasons we're being given.

For example, looking at the high-level functionality of the brain and comparing it with the transistors of a computer is an absolute give-away that the author isn't going to let the facts get in the way of a good story. The low-level mechanics of the brain (the chemical and electrical signalling) can be reasonably compared to the low-level mechanics of a computer, because it is valid to compare like with like. For the same reason, it would be fair to compare the Operating System of a computer to the ancient "reptilian" core of the brain. Both are designed for housekeeping operations and are used by the higher levels to mask implementation details. And so on up through the layers.

It should also be kept in mind that the human brain is capable of almost ten times the throughput of a top-of-the-line supercomputer. Given that one of the limiting factors of parallel architectures is the interconnect, it does prove that our networking technology is still extremely primitive. This is important, because it is going to be hard to build a machine that can "think" like a human if we have the "neural" interconnects of a Diplodocus.

At the current rate of technological progress, I do not believe we will have a computer powerful enough to model the human brain until 2015 or 2020. Even then, it'll be a Government-owned supercomputer likely used for weapon simulation. We won't see Strong AI researchers get hold of such machines until maybe 2060 and (if the usual development patterns hold) nobody will have any idea how to turn the raw computing power into something useful until 2100 at the earliest.

So, really, the earliest we could possibly really know (for certain) that the mind is (or isn't) like a machine is 2100. Anything stated with certainty before then is pure ego-stroking for the group of supporters attached with one camp or the other. Doubly so when it is provably and obviously intended to be deceptive.

The only problem I see with debating the matter from an intellectually honest standpoint until then is that current global warming models put most of the planet under water or under rainforest by 2100, which means that we might never really know the results of the research anyway.

Re:False presumption

[blair1q]

Get some of Carnap's books. Read them. There is a distinct difference between syntax (logic) and semantics (meaning). And there is no reason a computer can't understand both.

The logic of language is in its syntax. The meaning of language is in its semantics. But you can't develop the extra-syntactic information without applying logic to previously unknown words, so that they can be associated with named words later without being themselves named in a sentence.

What the human brain does, if it has any semantic experience stored, is try several semantic associations against the syntactic logic of a sentence until one "makes sense"; i.e., the inferred logic is not broken by the stated logic.

This process can be applied by a computer.

If you decide that your brain is somehow magical; that it is not a computer; then you are wrong.

And if you think that all computers are Turing machines, you're wrong about that, too.