2020/1 PSYCHOLINGUISTICS

15.2   Theory 1: Speech is essential for  thought   

15.2.1 Proponents of the theory

Proponents of this view hold that thought is a kind of behaviour that originates from speech production. Typically, such theories are held by Behaviourists who wish to get rid of mind and Mentalism in psychology, linguistics, and philosophy and to replace the notion of thought or cognition with something that is physically observable or potentially observable. The psychologists Watson, Skinner, and Staats, the linguists Bloomfield and Liberman, and the philosophers Ryle and Quine are but a few of the many who advocated such a conception. They define thought as subvocal speech or behaviour and not something mental, as in the traditional view of psychology.

The following quotations characterize the theory that thought originates from uttered speech:

The simplest and most satisfactory view is that thought is simply behavior – verbal or nonverbal, covert or overt. It is not some mysterious process responsible for behavior but the very behavior itself in all the complexity of its controlling relations, with respect to both man the behaver and the environment in which he lives.

(B. F. Skinner, 1957, p. 449)

The fully literate person has succeeded in reducing these speech movements    to the point where they are not even visible. That is, he has developed a system of internal substitute movements which serve him for private purpose, such as thinking and silent reading, in place of audible speech sounds.

(Leonard Bloomfield, 1961, p. 31, from a 1942 paper)

Articulatory movements and their sensory effects mediate between the acoustic stimulus and the event we call perception.

(Alvin Liberman, 1957, p. 122)

Liberman proposed the Motor Theory of Speech Perception, according to which, before we can understand speech, we must first repeat subvocally or internally what another person has said. Only by this prior motor act can we understand speech.

15.2.1 Inadequacies of the theory

We would like to raise objections with regard to the adequacy of this theory. Sometimes, given the abstract and intangible nature of the subject matter, not all objections can be expected to be definitive. Our principal aim, how- ever, is to provide a number of objections whose combined effect is to raise reasonable doubts about the theory in question. We shall raise six objections to this theory. They are: (1) Children having no speech production can com- prehend speech and think; (2) Speech comprehension, which implies thought,

develops before speech production in normal children; (3) Simultaneously speaking aloud while thinking about something different commonly occurs in everyday life; (4) Telling a lie; (5) Meaning and thought occur without behaviour; and (6) Interpreting between languages can be done. Each of these objections will now be discussed in turn.

15.2.1.1 Children having no speech production can comprehend speech and think

While the ability to utter speech in appropriate situations is a good indicator of language knowledge, the absence of the ability to produce speech may not indicate a lack of language knowledge. There are many hearing persons who are born mute. People such as these may be born with cerebral palsy or some other abnormality that prohibits them from articulating speech. In Chapter 1, we described among others the cases of Nolan, the noted Irish writer, and Rie, the 3-year-old Japanese child who learned to read words, with understanding, that she could not say. None of these persons could speak. Were these people able to think? Let us answer this question by implica- tion, since a direct answer would require a lengthy and contentious thesis on the nature of thought. If a person can comprehend the meaning of speech, that person must have the ability to think. It would be ludicrous to have to argue that persons exist who understand the meaning of speech but are unable to think. Surely the ability to answer items on an intelligence test

presupposes the existence of thought in the person taking the test.

It must therefore be concluded that persons without the ability to speak can think. The notion that speech production is necessary in order to think is clearly false.

15.2.1.2 Speech comprehension, which implies thought, develops before speech production in normal children

As was discussed in Chapter 1, the developmental process is that speech comprehension precedes speech production. It is the pattern that continues throughout the acquisition process (Ingram, 1989), whether it be for first words (Clark and Barron, 1988), elaborate syntax such as passives (Golinkoff and Hirsch-Pasek, 1995), or the later acquisition of idioms and figurative speech (Levorato and Cacciari, 1995).

The comprehension and production processes develop in a parallel mode with production always trying to keep up with comprehension. As the child acquires an aspect of language in comprehension, the child can then try to figure out how to use it in production. The child attempts to co- ordinate production with respect to the system that has been developed for understanding (Clark and Hecht, 1983).

Thus, Huttenlocher (1974), who studied four young children aged 10 to 13 months over a six-month period, found that they were able to comprehend speech at a level beyond that to which they had progressed in production.

Similarly, Sachs and Truswell (1978) found that children who could only produce single-word utterances (they were at the one-word stage of speech production) nevertheless could understand syntactic structures composed of more than one word. The outcome was the same for the child in the Steinberg and Steinberg (1975) research, where a 2-year-old boy learned to read (under- stand the meaning of) many written words, phrases, and sentences before he was able to say them.

That children would not be able to utter words or sentences for the purpose of communication (not simple imitation), without gaining a prior understand- ing of speech, is surely to be expected. One could not use speech meaning- fully unless one knew what meaning such speech had.

Thus, it must be concluded that for normal children as well as for mute- hearing children, speech comprehension is the basis for speech production in     the mind. Since the ability to comprehend speech implies the existence       of thought, it therefore must be concluded that speech production is not necessary for thought.

15.2.1.3      Telling a lie

Neither would telling a lie be possible if thought is a kind of speech. The very essence of a lie is saying one thing while thinking something quite different. Behaviourists wish to use one process of sentence creation for both processes (saying and thinking) simply by distinguishing the overt (speaking aloud) sentence from the covert (speaking to oneself or subvocally) sentence. However, because there is only one sentence-making apparatus, an overt pronunciation of one sentence and the covert pronunciation of an entirely different sentence (the covert sentence being the Behaviourist’s idea of thought) cannot occur simultaneously. Clearly, a valid psycholinguistic theory must allow two distinct processes with different content to occur at the same time. The issue of lying demonstrates that the Behaviourist cannot define thought out of existence!

15.2.1.4      Meaning and thought occur without behaviour

Behaviourists: behaviour of the body is essential for thought

In his theory of the origin of thought, Skinner suggested that behavioural responses could be the basis of thought in addition to speech utterances. Such behavioural responses could be muscular or glandular in nature. It seems that Skinner was influenced by the work of some Behaviourist psy- chologists who were his contemporaries around the 1950s. Experiments showed, to the delight of Behaviourist psychologists, that changes in electrical potential occurred in certain parts of the bodies of subjects when the subjects were instructed to think of certain motor activities. For example, changes in electrical potential in the musculature of the right arm occurred in response to instructions to think about lifting that arm. They concluded that thinking