[This is a guest post by Talia's girlfriend Annie, who is maintaining this blog while Talia is away at Middlbury Language Academy. Also, I'm sorry this post is a couple days late; I've been really busy this week.]
The “Chinese room” is a famous thought experiment in philosophy of mind that argues that, no matter how well the output of a computer program imitates the output of human thought processes, a computer can never attain true consciousness or understanding. The argument was first articulated by philosopher John Searle in his 1980 paper “Minds, Brains, and Programs,” and runs as follows:
The “Chinese room” is a famous thought experiment in philosophy of mind that argues that, no matter how well the output of a computer program imitates the output of human thought processes, a computer can never attain true consciousness or understanding. The argument was first articulated by philosopher John Searle in his 1980 paper “Minds, Brains, and Programs,” and runs as follows:
Suppose that I'm locked in a room
and given a large batch of Chinese,writing. Suppose furthermore (as
is indeed the case) that I know no Chinese, either written or spoken,
and that I'm not even confident that I could recognize Chinese
writing as Chinese writing distinct from, say, Japanese writing or
meaningless squiggles. To me, Chinese writing is just so many
meaningless squiggles. Now suppose further that after this first
batch of Chinese writing I am given a second batch of Chinese script
together with a set of rules for correlating the second batch with
the first batch. The rules are in English, and I understand these
rules as well as any other native speaker of English. They enable me
to correlate one set of formal symbols with another set of formal
symbols, and all that "formal" means here is that I can
identify the symbols entirely by their shapes. Now suppose also that
I am given a third batch of Chinese symbols together with some
instructions, again in English, that enable me to correlate elements
of this third batch with the first two batches, and these rules
instruct me how to give back certain Chinese symbols with certain
sorts of shapes in response to certain sorts of shapes given me in
the third batch. Unknown to me, the people who are giving me all of
these symbols call the first batch a "script,"
they call the second batch a "story," and they call the
third batch "questions." Furthermore, they call the symbols
I give them back in response to the third batch "answers to the
questions," and the set of rules in English that they gave me,
they call the 'program." Now just to complicate the story a
little, imagine that these people also give me stories in English,
which I understand, and they then ask me questions in English about
these stories, and I give them back answers in English. Suppose also
that after a while, I get so good at following the instructions for
manipulating the Chinese symbols and the programmers get so good at
writing the programs that from the external point of view – that
is, from the point of view of somebody outside the room in which I am
locked – my answers to the questions are absolutely
indistinguishable from those of native Chinese speakers. Nobody just
looking at my answers can tell that I don't speak a word of Chinese.
Let us also suppose that my answers to the English questions are, as
they no doubt would be, indistinguishable from those of other native
English speakers, for the simple reason that I am a native English
speaker. From the external point of view-from the point of view of
someone reading my "answers"
– answers to the Chinese questions and English questions are
equally good. But in the Chinese case, unlike the English case, I
produce the answers by manipulating uninterpreted formal symbols. As
far as the Chinese is concerned, I simply behave like a computer; I
perform computational operations on formally specified elements. For
the purposes of the Chinese, I am simply an instantiation of the
computer program.
Searle argues that, just as his
ability to manipulate symbols to produce what looks like fluent
Chinese would not mean he understands Chinese, neither would a
computer’s ability to do the same mean that it understands Chinese
(or whichever language it is imitating).
Now,
I’m not going to mince words here: I think this argument is
completely wrong. But it’s wrong in a way that’s worth
considering at length, because I think it illuminates a common error
in how many people think about computers – and,
for that matter, about minds.
In
identifying himself with the computer in this thought experiment,
Searle is implicitly treating the computer, and thus the “mind”
of a hypothetical artificial intelligence, as isolable from the
programs that are given to it. In Searle’s formulation, programming
a computer is analogous to giving a set of instructions to a human
who then blindly carries them out. The human’s mind processes the
instructions and moves the body so as to carry them out, but doesn’t
gain deeper understanding from them.
But
I think Searle is drawing
his conceptual boundaries in the wrong place. By placing a human in
the Chinese room as the agent carrying out the instructions, Searle
has biased himself and his audience in favor of his interpretation.
We all know that humans have conscious, thinking minds, so we
naturally assume that the human is the only thing in the Chinese room
that could be doing any thinking. But is this necessarily the case? I
would argue that no, it’s not. Searle’s
main error, in my view, is his identification of the human in the
Chinese room with the computer. The human is actually carrying out a
role more akin to that of a processor – the part of the computer’s
physical hardware that translates the information in a program into
actions. Treating the processor as if it were the entire computer
completely overlooks the role played by the information in the
programs themselves. Treating the processor as the location of an
artificial intelligence’s “mind”, with no reference to the
information being processed, is like looking for the human mind in
the physical architecture of individual neurons without paying any
attention to the electrochemical
state of those neurons and the information encoded by that state.
In the analogy between mechanical minds and human minds, programming
a computer isn’t like giving a human a list of instructions –
it’s more like giving them a psychiatric drug that directly
modifies the functioning of
their brain.
In
the Chinese room, the human is embedded in a larger system that
includes the rule books the
human is using to process the Chinese writing. The human may not
understand Chinese, but I would argue that this larger system does.
If this system contains all the information necessary to recognize a
semantically meaningful input and produce an equally meaningful
output in response, and to do so with all the robustness and fluidity
of a native human speaker of the language, I would be entirely
comfortable saying that this system understands the language. If we
are assuming that anything capable of understanding a language must
qualify as a mind, then the Chinese room represents one mind embedded
inside another one.
If
this argument is hard for you to intuitively grasp, it might help to
think about what the physical architecture of the Chinese room would
have to look like. At my current job, I work on programs that process
language, and the code for these programs is really
long.
I only work on a small portion of it, but I’d guess that if the
whole thing were printed out, it
could fill up a few books. And what these programs are capable of is
not even close to what the hypothetical program in Searle’s thought
experiment would have to be capable of. The programs I work on take
a piece of text as input and identify key words and phrases that
relate to a particular domain of interest. Most of them stop there,
but the most loquacious among them will spit out one of a few
pre-written phrases to prompt the user for more input. That’s a far
cry from producing fluent speech that’s indistinguishable from that
of a native speaker. A program that could do that would have to be
vastly longer and more complicated than any of the programs I’m
familiar with.*
And in the Chinese Room experiment, we’re not even talking about a
digital representation of these programs, but an analog one, written
out in English on physical sheets of paper. Theoretical physicist
Scott Aaronson, in his book Quantum
Computing Since Democritus,
describes what this might look like:
The third thing that annoys me
about the Chinese Room argument is the way it gets so much mileage
from a possibly misleading choice of imagery, or, one might say, by
trying to sidestep the entire issue of computational
complexity purely
through clever framing. We’re invited to imagine someone pushing
around slips of paper with zero understanding or insight, much like
the doofus freshmen who write (a + b)^2 = a^2 + b^2 on their math
tests. But how many slips
of paper are we talking about?
How big would the rule book have to be, and how quickly would you
have to consult it, to carry out an intelligent Chinese conversation
in anything resembling real time? If each page of the rule book
corresponded to one neuron of a native speaker’s brain, then
probably we’d be talking about a “rule book” at least
the size of the Earth, its pages searchable by a swarm of robots
traveling at close to the speed of light. When you put it that way,
maybe it’s not so hard to imagine this enormous Chinese-speaking
entity that we’ve brought into being might have something we’d be
prepared to call understanding or insight.
Much
more complicated than a guy in a room shuffling papers around, no?
Citations:
Searle, John. "Minds, Brains, and Programs." The Behavioral and Brain Sciences, Vol. 3, Cambridge University Press, 1980.
Aaronson, Scott. Quantum Computing since Democritus. Cambridge University Press, 2013.
*Chatbots
that can produce fairly naturalistic output do exist (eg. Siri or
Cortana), and they are indeed more complex than the programs I work
on, but even they haven’t achieved the level of fluency described
in Searle’s experiment. The most advanced one I’m aware of is
Microsoft’s Tay, and at its most fluent it produced a fairly convincing impression of an internet troll. Whether this can be
considered human-level linguistic proficiency is, shall we say, open
to interpretation.
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