These are excerpts and elaborations from my book "The Nature of Consciousness"
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Pinker spoke of a language instinct
rather than of a universal language. He noticed how inherently, and
naturally, complex language is. It is virtually impossible for a community of
human beings to develop a "simple" language. As Pinker puts it:
"there are stone-age societies, but there is no such thing as a stone-age
language". All languages, even in the most primitive societies, are
complex, convoluted, redundant, full of exceptions, synonyms and ambiguities.
His explanation is that humans are equipped with a "language
instinct" that makes them reinvent language generation after generation. The way children learn a
language seems to be largely independent of what their parents teach them. For
example, children use grammatical forms that they never heard from their
parents. The ability of children to learn a language depends on the extent to
which their brains are biased towards some kinds of phrases (e.g., noun
phrases) and equipped with some kinds of procedures. Pinker thinks that language is merely
a (very limited) medium to pack our thoughts and broadcast them to our fellow
humans. In the process, we lose most of the reasoning that went on in our
brains. Pinker thinks that the mental representation of what we are saying is
way more complex and subtle, and just cannot be expressed in words. Words are
an effective way to deliver the essential part of the meaning in a reasonable
amount of time. Our thoughts are not verbal: they are mental representations of
the kind that resembles Jerry Fodor's "mentalese". And this mentalese is a genetic fact: we
inherit it when we inherit human genes. It is universal. We all reason the same
way. We think in mentalese, not in English or Chinese. It is only when we have
to pack information for another human being that we use the language of our
community (e.g., English or Chinese), and in doing so we have to limit our
message to what can be said in that language. Pinker therefore sides with the school
of the "physical symbolic processor": a mind is a purely syntactic
processor of symbols, and the "intelligence" of that mind arises from
processing the symbols, just like the Turing machine is capable of solving
(almost) every problem by moving symbols around, without actually
"knowing" what problem it is solving (or even that it is solving a
problem). Pinker's point is that mental representation is a powerful invention. Once we
equip something with the ability to represent the world through symbols that
can be processed in some logical way, that something is suddenly endowed with
the power to solve even the most complex of problems. Mental representation
sounds indeed miraculous. The symbols are not intelligent. The algorithm to
process them is not intelligent. But the result is intelligent. In fact, the
result "is" intelligence itself. Language and thought have
little in common, according to Pinker: "knowing a language is knowing how to translate mentalese into
strings of words, and viceversa". People without a language are still
thinking in mentalese. Pinker notes that mentalese might
actually be simpler than the languages we speak, because it doesn't have to
deal with the oddities of spoken language (such as pronouns and indexicals) or
with pronunciation. Presumably, Pinker thinks that the complexity of spoken
languages evolved because it helps communicate the essential very quickly. Phonetic perception itself
is part of the language instinct. Sentences are made of words, words of
morphemes, and morphemes of phonemes. And phonemes are fundamentally different
from the other components of language, because they do not combine according to
a grammar: they represent the analogic to digital interface. At some point in evolution,
the mouth and the ear developed additional functions: to help utter sounds and
to help to "understand" sounds. Pinker claims that we can hear
"words" where there are just sounds because phonetic perception is a
sixth sense, another piece in the puzzle of the language instinct. Our brains
are hardwired to recognize "meaningful" words out of a stream of
"meaningless" sounds (there are actually no meaningless sounds, and,
according to Pinker's own theory, words are not really meaningful, but Pinker uses
"meaningful" as in "useful for the purpose of reacting to a
sentence"). Pinker shows how we use an assembly of organs to create the
sounds of sentences. Recognizing a phoneme is much more difficult than dealing
with grammar, so much so that no machine has been built yet that can recognize
speech the way the human brain does. First of all, there is hardly any
separation between words when we speak: there is a continuous flow of sounds.
Secondly, different speakers pronounce the same words in different ways.
Thirdly, the same speaker can pronounce the same word in different ways
(depending on whether she is sleepy or not, angry or not, in a hurry or not).
Machines that try to recognize speech have to be "trained" to the
voice of a particular speaker, and can generally recognize only a small subset
of the vocabulary (usually, only a dozen of words, instead of the tens of
thousands that the human brain recognizes effortlessly). Clearly, the wiring of
the human brain is the secret to recognizing speech. There are other features of
the human brain that are difficult to replicate with a machine, and they all
have to do with "analogic" versus "digital" reasoning.
Uttering or listening to speech is a function very similar to grasping an
object, another difficult act for a machine. The brain does not simply
calculate distance and angle to program the movement of the arm. The movement
of the arm and of many other organs, from the joints of the fingers to the
muscles of the eyes are continuously refined as the movement itself takes
place. A complex process of feedback makes sure that the movement achieves its
goal. Pinker shows that something similar happens when we speak: a number of
organs cooperate in making the sounds of words, and the sound wave is refined
as it is being uttered; and viceversa when the sound wave is being heard. Thus
speech belongs to the general class of "motor control". Just like
with other kinds of motor control, the "expectation" contributes to
the success of the operation. If one "expects" to hear something,
then she is more likely to hear it. Since we expect a speaker to make sounds
that are words in our language, we are more likely to detect them, even though
the words are not coded in the exact same sound wave each and every time.
Speech recognition is greatly facilitated if the hearer continuously guesses
what the speaker is trying to say. The secret of speech is not in its
"digital" workings (how the brain dissects and processes its
constituents) but in its "analogic" workings (how the brain
continuously readjusts the process to sculpt an output that matches the input). If all humans are equipped
with the same universal grammar, a legitimate question is why are there so many
languages instead of just one. Pinker's answer is similar to the answer to the question of why are there so
many species of animals if all animals are equipped with the same genetic code:
it's the way evolution works, namely variation is an inherent element of
evolution. Linguistic variation boosts cultural evolution the same way that
genetic variation boosts biological evolution. New languages are born the same
way that new species are born, through a process of variation, heredity and
isolation. (This similarity had originally been pointed out by Darwin himself). Pinker does not
elaborate on the linguistic equivalent of "natural selection", i.e.
the role played by the "environment" (which, in the case of language,
is the society of other speakers), but language too is subject to environmental
pressure. If a child utters a meaningless sentence that brings no benefit (or
is even harmful in achieving the goal), that sentence will die out. On the
other hand, novel sentences or grammatical constructs or idiomatic expressions
that turn out to be very effective are inherited by other speakers and spread
throughout the population of speakers. This is the equivalent of what natural
selection does to organs of bodies. Pinker calls it "language
instinct". Like all instincts, it must be implemented somewhere in the
brain, and that implementation must be dictated by some genes of the human
genome (and neurologists proved that language is implemented in the left
hemisphere). That is why Pinker thinks that animals cannot speak language,
"real" language: they lack the genes, and therefore they lack the
brains. They can certainly be trained to recognize and react to certain sounds
(although never with the same dexterity of a child) but they lack the
"discrete combinatorial system" that would enable them to understand
"other" sentences besides the ones they have been trained to react
to. Children do not simply repeat the sentences that they have been taught:
children come up with their own sentences. What children have learned is
"language", not just a few words or a few sentences. That is what
animals cannot learn. Animals can learn to react to the sentence "Kiss
me" and "Dog", but they cannot understand the sentence
"Kiss the dog". Even less likely is that they can understand the
sentence "Kiss her". And even less likely to reply to a simple
question such as "Why?" Children, instead, rapidly learn to deal with
sentences such as "Why aren't you nice to her?" even if they never
heard those words before in that specific sequence, as long as they have
learned what "nice" means, and what pronouns stand for, and what is
expected by a "why". Neurally speaking, Pinker thinks that human language is
ultimately controlled by the neocortex, whereas animal "language" is
controlled by the evolutionary older structures in the brain stem and in the
limbic system. Humans too have this primitive form of language controlled by
the same ancient brain structures, but those are the kind of sounds that cannot
be "combinatorially combined", for example a scream of terror or a
burst of laughter. Human language is not a combination of these primitive
sounds, but a different process altogether of syntax, morphology and phonology
that takes place in a different region altogether of the brain. Back to the beginning of the chapter "Language: Minds Speak" | Back to the index of all chapters |
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