3. Descartes.
It would be more absurd to regard
Descartes as a behaviorist than
Hobbes; for he was
notorious for the dualism of mind and matter which
he postulated. But, as a matter of fact, both his dualism
and his
assumptions about scientific method did much
to create the climate of
opinion which made behav-
iorism possible,
if not almost inevitable.
Descartes held that there are two sorts of substances
in the world, mental
and physical. If the behavior of
these substances was to be scientifically
studied, as-
sumptions about them had to be
made explicit and
exhaustively analyzed until clear and distinct ideas
were arrived at, which were simple in the sense that
no further analysis of
them was possible. In the case
of ideas about material objects, for
instance, the scien-
tist eventually arrived
at the simple ideas of extension,
figure, and motion. If certain of these
simple ideas were
combined, relationships could be grasped between
them which served as postulates for a deductive system,
as in geometry.
Thus the understanding of bodies and
of minds respectively rested upon
clear and distinct
ideas which had no features in common. Descartes'
problem about the relationship between mind and body
derived from the fact
that, though in our confused
everyday experience we are aware of
interaction, as
when our limbs move because of our intentions, no
clear and distinct idea can be formed of the manner
of this union. Such
perspicuous ideas are only forth-
coming in
the spheres of the mental and the physical
when they are proceeding
independently of each
other—as in logical reasoning on the one
hand or in
reflex movements on the other.
Descartes' dualism and his assumptions about scien
tific method thus gave rise to two traditions of enquiry
which
came to be pursued more or less independently
of each other. On the one
hand the human body, which
was regarded as functioning mechanically right
up to
the level of instinctive behavior and simple habits, be-
comes a fit subject for objective study.
Harvey had
made a splendid advance in this field with his mechan-
ical theory of the circulation of the
blood. On the other
hand, the mind, by which Descartes meant mainly
the
higher thought processes and the will, could only be
studied
introspectively. The consequence of Descartes'
dualism was, therefore, the
school of mechanistic biol-
ogy and reflexology
on the one hand and the intro-
spective
school of psychology on the other, which
reached its culmination about 250
years later in the
laborious experimental work of Wundt and Titchener.
It was against the assumptions of the introspective
school that Watson
revolted—their assumptions about
both introspective method and
the “stuff” of conscious-
ness which he claimed they were trying to study by
this method.
And when he revolted he fell back on
the other tradition stemming from
Descartes: mecha-
nistic biology and
reflexology. All he did was to at-
tempt to
extend its domain to the level of thought and
action which had previously
been regarded as “mental”
and hence to be studied by
introspective methods. And
when Watson theorized about behavior he was
un-
wittingly Cartesian in his approach.
He thought that
the complex phenomena of behavior could be ex-
plained by analysis into clear and distinct
units of
behavior—simple reflexes.