Technical and non-technical language

[From Bill Powers (951010.2330 MDT)]

RE: Technical and non-technical language

One of the important difficulties that exists between PCT and
psychological disciplines is a misunderstanding about the kind of
explanatory language that is used in PCT. In looking for other materials
in the archives, I've run across repeated examples of this difficulty,
of which the following words are examples:


These words represent attempts to express concepts in terms of ordinary
language, where meanings are ambiguous and shift with context. These are
words which we first encounter not in science but in literature and
conversation, and not in college or graduate school, but in grammar
school and high school. They are fundamentally non-technical terms
reflecting private experience and not a formal system of meanings.

Psychology generally works in terms of words like these, because these
are the terms in which people normally express their experiences. The
only truly technical terms in psychology, terms which have formal
definitions that remain the same under all circumstances, are borrowed
from other disciplines: mainly physics, chemistry, and mathematics. But
even these borrowed words often have meanings that tend to drift as soon
as they are put into use by psychologists: separation no longer means
just the distance between two points, or equally well the rate of
increase of distance, but a loss of support and comfort, an overcoming
of a desire to cling, and so forth. Stress no longer means just the
degree of elongation under a stretching force, but a psychological and
physiological state involving "tension", "anxiety", or an approach to

One argument particularly caught my eye. It was about "prediction." A
prediction, in informal language, is a statement made about what is
going to happen before it happens. A gambler predicts that the dice will
show a 3 on the next roll. A handicapper predicts that a horse that has
run well in cold weather and on a muddy track will run well the next
time the conditions are the same. A weather forecaster predicts what the
weather for the next five days will be. A mother predicts that her son
will grow up to be a doctor. A magician predicts that when you open the
envelope, it will contain the five of hearts. A defense attorney
predicts to the jury that it will return an acquittal. B. F. Skinner
predicts that he is going to mail a letter. A palm-reader predicts that
you will meet a tall dark stranger.

The word "prediction" designates a large class of processes held
together only by a vague similarity: they all treat the future in some
way. But the way they treat it varies from guessing based on a feeling,
to assuming that what has happened before will happen again, to
extrapolating current trends to future states, to expressing a hope, to
describing certain knowledge, to attempting to influence an outcome, to
deducing a logical conclusion from premises, so saying what someone
wants to hear. All these processes are treated as if they were examples
of the same thing, by calling them all "predictions." Clearly, classing
one process as a prediction does not mean that it actually has anything
in common with other processes that are given the same label and put in
the same class. But informal language does not take those differences
into account.

This is typical of non-technical language. The fact that the same word
is used under different circumstances is taken to mean that the
different circumstances must have something in common. If the word
exists, it must refer to something real, some essence of the situation,
some hidden truth of nature. If you speak of a distressed child and a
distressed antique desk, there is a sense that the word "distressed"
really captures something that the child and the desk have in common.
This sense is most evident when people start arguing about what a word
"really means."

The specific argument I came across was whether a perceptual signal plus
its first derivative constituted a prediction. There is certainly no
ambiguity about the meaning of p + dp, but there is considerable
ambiguity about "prediction." Does p + dp really belong to the class of
processes also exemplified by a magician predicting that you will find
the five of hearts in the envelope (which he put there himself)?
Clearly, it is one of the types of processes that are covered by the
term, but the same term covers completely different processes as well.
All that we gain by calling p + dp a "prediction" is a potential
confusion of a specific process with other processes of totally
different kinds.

p + dp is an expression in a technical language. Specifying this form of
an input function for a control system, plus similar specifications for
the rest of the system, allows making a unique model which will behave
in a specific way. But if we just said that the input function carried
out a "prediction," we would have no idea how the system would behave.
If this input function predicted that the future would resemble the
average behavior in past under similar circumstances (as the handicapper
does), the perceptual signal would be a constant and there would be no
control. If the input function picked some favorable or lucky value of
the perceptual signal like 3 and predicted that this value would appear
next, as the mother predicting that her son will be a doctor does or as
the gambler does, again we would have a system behaving in a very
strange way. We can't just propose that some process that falls under
the term "prediction" is taking place; we have to make a specific
proposal. And if we do that, by saying that the input to the comparator
is p + dp, we have said all that is necessary to define the perceptual
function and its behavior, and we have said it unambiguously.

What we find on csg-l is often an argument that is motivated (on one
side at least) by the desire to find a common-language or psychological-
language equivalent of some process defined in the technical language of
PCT. It's as though the technical description is treated as being vague
or ambiguous, and the attempt is to find out what that description
"really means" -- which comes down to finding a term in the vague and
ambiguous language of the layman which includes, among its many other
meanings, the simple and precise meaning defined under PCT.

This, of course, works exactly against the objectives of PCT, which are
to find unambiguous terms to replace the ambiguous terms in which
behavior has traditionally been described. The term "reference signal"
has a single clear meaning which defines the way such a signal
participates in a control process. Reference signal does not "really
mean" goal, desire, want, hope, aim, objective, purpose, intention, or
wish. Rather, all those other layman's terms, which refer to many side-
issues and connotations, refer in common to only one basic property: the
property that we give to a reference signal in the technical model.

My aim is to replace the vague language of the layman, which
psychologists use in lieu of a technical language, with terms that have
clear meanings that do not change with circumstances. Those are the only
kinds of terms in which a science of behavior can be couched.



Bill P.