Corrections to the blogosphere, the consensus, and the world

Tuesday, September 19, 2006

Blogging Lovaas, 2

So, on with the second paragraph.
Any one of the behaviours mentioned, such as language, may be broken down into a large number of separate behaviours, yielding more precise measurements and requiring different kinds of treatments.

No. Language is not an assemblage of behaviours, in any meaningful sense of 'behaviour'. Chomsky blew Skinner away on just this issue, in 1959 - "A Review of B. F. Skinner's Verbal Behavior" in Language, 35, No. 1 (1959), 26-58.

I had intended this review not specifically as a criticism of Skinner's speculations regarding language, but rather as a more general critique of behaviorist (I would now prefer to say "empiricist") speculation as to the nature of higher mental processes.....
The conclusion that I hoped to establish in the review, by discussing these speculations in their most explicit and detailed form, was that the general point of view was largely mythology, and that its widespread acceptance is not the result of empirical support, persuasive reasoning, or the absence of a plausible alternative.

Lovaas shares Skinner's "general point of view". As a result, he shares also in Chomsky's brickbats.

Skinner ..... utilizes the experimental results as evidence for the scientific character of his system of behavior, and analogic guesses (formulated in terms of a metaphoric extension of the technical vocabulary of the laboratory) as evidence for its scope. This creates the illusion of a rigorous scientific theory with a very broad scope, although in fact the terms used in the description of real-life and of laboratory behavior may be mere homonyms, with at most a vague similarity of meaning. To substantiate this evaluation, a critical account of his book must show that with a literal reading (where the terms of the descriptive system have something like the technical meanings given in Skinner's definitions) the book covers almost no aspect of linguistic behavior, and that with a metaphoric reading, it is no more scientific than the traditional approaches to this subject matter, and rarely as clear and careful.

Chomsky's demolition of behaviourism is so lapidiary that the temptation to quote in extenso is overwhelming.

What has been hoped for from the psychologist is some indication how the casual and informal description of everyday behavior in the popular vocabulary can be explained or clarified in terms of the notions developed in careful experiment and observation, or perhaps replaced in terms of a better scheme. A mere terminological revision, in which a term borrowed from the laboratory is used with the full vagueness of the ordinary vocabulary, is of no conceivable interest.

However, much of the basic structure of ABA - in particular, the notion that language has to be specifically taught element by element, behaviour by behaviour - is directly descended from Skinner's ideas.

Similarly, it seems quite beyond question that children acquire a good deal of their verbal and nonverbal behavior by casual observation and imitation of adults and other children. It is simply not true that children can learn language only through "meticulous care" on the part of adults who shape their verbal repertoire through careful differential reinforcement, though it may be that such care is often the custom in academic families. It is a common observation that a young child of immigrant parents may learn a second language in the streets, from other children, with amazing rapidity, and that his speech may be completely fluent and correct to the last allophone, while the subtleties that become second nature to the child may elude his parents despite high motivation and continued practice. A child may pick up a large part of his vocabulary and "feel" for sentence structure from television, from reading, from listening to adults, etc. Even a very young child who has not yet acquired a minimal repertoire from which to form new utterances may imitate a word quite well on an early try, with no attempt on the part of his parents to teach it to him. It is also perfectly obvious that, at a later stage, a child will be able to construct and understand utterances which are quite new, and are, at the same time, acceptable sentences in his language. ... I have been able to find no support whatsoever for the doctrine of Skinner and others that slow and careful shaping of verbal behavior through differential reinforcement is an absolute necessity. If reinforcement theory really requires the assumption that there be such meticulous care, it seems best to regard this simply as a reductio ad absurdum argument against this approach.

What Lovaas has done is to take the structure that Skinner said ruled everybody and restricted it to the special case of people with developmental delay. This has not removed the internal contradictions of the program.

It is not easy to accept the view that a child is capable of constructing an extremely complex mechanism for generating a set of sentences, some of which he has heard, or that an adult can instantaneously determine whether (and if so, how) a particular item is generated by this mechanism, which has many of the properties of an abstract deductive theory. Yet this appears to be a fair description of the performance of the speaker, listener, and learner. If this is correct, we can predict that a direct attempt to account for the actual behavior of speaker, listener, and learner, not based on a prior understanding of the structure of grammars, will achieve very limited success. The grammar must be regarded as a component in the behavior of the speaker and listener which can only be inferred, as Lashley has put it, from the resulting physical acts. The fact that all normal children acquire essentially comparable grammars of great complexity with remarkable rapidity suggests that human beings are somehow specially designed to do this, with data-handling or "hypothesis-formulating" ability of unknown character and complexity.

Do pwdd have hhypothesis-formulating ability, as described here by Chomsky, or not? If they do not, how is it possible to (in Lovaas' words) 'teach them to understand'? If they do, what is the justification for teaching them as if they did not?

Skinner himself said
"A child acquires verbal behavior when relatively unpatterned vocalizations, selectively reinforced, gradually assume forms which produce appropriate consequences in a given verbal community". "Differential reinforcement shapes up all verbal forms, and when a prior stimulus enters into the contingency, reinforcement is responsible for its resulting control.... The availability of behavior, its probability or strength, depends on whether reinforcements continue in effect and according to what schedules." That's what Lovaas, in effect, tries to do. And that's where, to return to the sentence we started with, we have to ask how one breaks down language into verbal behaviours. Back, again, to Chomsky.

What are in fact the actual units of verbal behavior? Under what conditions will a physical event capture the attention (be a stimulus) or be a reinforcer? When are stimuli "similar"? And so on. The use of unanalyzed notions like similar and generalization is particularly disturbing, since it indicates an apparent lack of interest in every significant aspect of the learning or the use of language in new situations. No one has ever doubted that in some sense, language is learned by generalization, or that novel utterances and situations are in some way similar to familiar ones. The only matter of serious interest is the specific "similarity." Skinner has, apparently, no interest in this.

Neither does Lovaas.

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