Re: What Is Psychology?

From: S.Harnad (harnad@coglit.soton.ac.uk)
Date: Fri Nov 07 1997 - 14:02:16 GMT


> From: Catriona Barrett <chb197@soton.ac.uk>
>
> Psychology is the Science of Mental Life, both of it's phenomena and of
> their conditions...The Phenomena are such things as we call feelings,
> desires, cognition, reasoning, decisions and the like. (William James,
> 1890)

The word "phenomena" (pl.) has two very different meanings: One meaning
is just about the same as "data/evidence/observations/facts." The
phenomena of Physics are things like apples falling (gravity), metals
attracting (electromagnetism) and billiard balls banging into one another
(mechanics).

In Psychology, "phenomena" in this first sense are also the data we can
all observe: People can move, see, hear, walk, talk, reply, etc.

But there is a second sense of "phenomena" which refers to what it
FEELS like for a person to move, see, hear, think, understand, etc.
This is not the kind of objective observation that any observer can make:
It is a special kind of "observation" (introspection) that each person
can only make for himself, for his own phenomena: I can't see how you
see red; I can only see how I see red. (Probably they are the same,
though no one can be sure; besides, there are other feelings -- like
guilt -- that I have no way of knowing whether or not you really feel.
One question about Louise Woodward is whether or not she really feels
she is innocent of killing the baby; no one knows except her, and maybe
SHE doesn't even know any more.)

> This century, however, many psychologists, in particular the American
> J.B. Watson, began to question the validity of these methods. He
> believed that it was impossible to either prove or disprove the results
> obtained by introspection. If one person's introspection produces
> different results form another, it does not necessarily mean that one
> set of results is correct and the other is incorrect. As a result
> Watson suggested that psychologists should confine their studies to
> what can be measured and observed by more than one person, behaviour.

Watson was right about introspection as a source of DATA: I can't observe
what is going on in your mind: all I can observe is what you DO; how you
act, rather than how you feel.

But Watson and the behaviourists were wrong about what Psychology had to
do to make theirs a science like any other: We only have behaviour (and
perhaps also brain measurements) as data; we can't look in the mind of
others to observe directly what is going on in there (even with the help
of the brain images that have lately become possible); moreover, there
would be no point in looking into other peoples' minds, because we
already know from looking into the only mind we can look into -- our own
-- that whatever is going on there, it doesn't EXPLAIN anything. You can
introspect about how you go about remembering the name of your 5th form
school teacher, but all you can really say is that you somehow find it:
your mind gives it to you on a silver platter, just as it gives you all
the other things you can do and feel. But what the mind does not serve
you on the silver platter of introspection is the explanation of how it
manages to do all those remarkable things it can do.

To explain this requires a theory, just as the explanation of apples
dropping from trees and metals attracting one another required a theory
in Physics. Now a theory is allowed to make use of unobservable things
to explain the observations: We don't actually "see" gravity, the force
that pulls masses toward themselves. We see only the data of physics, the
phenomena (in the first sense) of everyday life. The explanation uses
theoretical concepts such as gravity, and, using them, it DOES manage to
explain the data -- explain them well enough not only so that we can
understand the causes and effects that underlie falling apples and
attracting magnets, but well enough so that we can apply those
theoretical concepts toward building things like bridges, toasters and
computers, in the applied branch of science called ENGINEERING.

So the behaviourists were right to say that only observables are data
(and that other minds are not observable), but they were wrong in going
on to suggest that there was no place for unobservables in the
theoretical, causal explanation of the data.

In Psychology, the data are behaviour (and brain data): What is THEORY in
psychology? Some think brain theory will explain the data of psychology;
others, as you will see, say we need not wait for brain science to come
up with the whole story: we can test theories with computers to see
whether they are able to explain our behavioural capacities.

Psychological theory is "reverse engineering": organisms already exist,
with many remarkable, unexplained capacities. It is Psychology's
responsibility to come up with the causal explanation of those
capacities. Two ways to test a reverse engineering theory are:
(1) build the system you claim to have explained, and see whether your
explanation really works. (2) SIMULATE or MODEL the system you claim to
have explained on a computer, and see whether your explanation really
works.

In other words, the role of the computer in contemporary Psychology is as
a THEORY-TESTER. As such, it is not much different from paper and pencil:
If you think you have a formula that well solve certain kinds of
equations, you test it out (using paper and pencil) to see whether it
really does solve those equations. You can test it yourself, by paper and
pencil, or using a computer. The case is similar with Psychological
Theory.

> Science can be defined in many ways but it has been proposed that there
> are certain criteria to be met. Firstly, there must be a definable
> subject matter, in other words, the range of objects or phenomena that
> are to be studied must be clearly defined. Secondly, there must exist a
> kind of theory construction and hypothesis testing. A theory can be
> defined as "a complex set of interrelated statements which attempts to
> explain certain observed phenomena". from this theory it must be
> possible to create testable statements about the relationship of two or
> more variables. It is these testable statements that are known as
> "hypotheses' and it is the hypotheses that are tested during scientific
> research. Thirdly, facts must be established through the use of
> "empirical' methods of investigation, in other words, observation,
> measurement and other objective methods. Lastly, attempts should be
> made to establish general laws or principles.

This explanation of science is correct, but very abstract: Kid-sib
would not have understood it! He needs examples. (Newton hypothesising
that the apple falls because of gravitational attraction is an example
of a theory in Physics; the hypthesis that appetite is controlled by a
mechanism similar to a thermostat would be an example of a theory in
Psychology.

(A theory consists of many hypotheses; a model is a simple theory.)

> psychology does have a
> definable subject matter, which is the study of the mind and behaviour.
> Secondly, the discipline of psychology does construct theories, for
> example, the theory invented by Piaget that children are born with a
> Language Acquisition Device that enables them to learn language.
> Psychology also tests its hypotheses, for example, by placing a child
> in an environment where no verbal communication is made at all and to
> see whether or not the child does learn language. This would determine
> whether language is an innate ability in children or whether it is
> learned through social interactions with others. Thirdly, the
> discipline of psychology does use empirical methods of investigation,
> such as observing and recording the behaviour of children in response
> to certain stimuli. Lastly, the discipline of psychology does attempt
> to establish general laws, for example, that the mind and thoughts and
> feelings in particular directly affect behaviour.

Good summary; kid-sib understood it!



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