2. E. C. Tolman.
One of the most influential and
forceful converts to behaviorism was
E. C. Tolman;
for he was calling himself a “purposive
behaviorist”
as early as 1920, though his definitive work entitled
Purposive Behavior in Animals and Man did not appear
until 1932. He aligned himself with the behaviorists
because he accepted
their central methodological doc-
trine about
the sort of evidence on which a scientific
psychology should be based. He
did not indulge, like
Watson and Weiss, in metaphysical assertions about
the
sorts of entities which there are in the world; he ad-
mitted that, at a common-sense level, men introspect
and manage well enough with mentalistic terms. What
he doubted, however,
was the adequacy of this termi-
nology for
scientific purposes. “Raw feels” are scien-
tifically useless, and mentalistic
terms can be translated
into the language of observable behavior. Tolman,
in
other words, was a conceptual behaviorist rather than
a
materialist, as well as being a behaviorist in his
explicitly stated
methodology.
In the conceptual sphere Tolman made at least three
contributions, two of
which were of permanent impor-
tance. Firstly
he called himself a purposive behaviorist
because he maintained that the
concept of purpose was
irreducible. As has been mentioned (sec. I, 2), he dis-
tinguished between the molecular and the molar level
of behavior, whose unity as segments of
behavior is
provided by the ends towards which movements persist
and
in the attainment of which they are docile. He
accused Watson of not
distinguishing clearly between
the molecular and the molar levels of
analysis and
maintained, against Hull, that behavior at the molar
level is an “emergent” which has descriptive and de-
fining properties of its own. Descriptions of
it cannot
be reduced to or deduced from analyses at the molecu-
lar level.
Secondly Tolman made rather bizarre attempts to
translate mentalistic terms,
which had application at
the molar level, into a behavioristic type of
termi-
nology.
“Consciousness” became “the performance of
a 'sampling' or 'running-back-and-forth' behavior.” He
even
suggested that Freudian personality mechanisms
can be translated into this
type of terminology.
Thirdly, Tolman introduced into psychological the-
ory the notion of intervening variables. Terms like
“instinct” had previously been used, e.g., by
McDougall, not simply to postulate that certain pur-
posive behavior patterns were unlearned; they also had
a
metaphysical dimension to them—a suggestion of
Aristotelian
entelechies, of dynamic mental atoms ac-
tivating behavior. Tolman argued that it was perfectly
legitimate
for a behaviorist to use a term like “drive”
which
did not denote an unobservable entity, but
which was a shorthand symbol for
stating a correlation
between antecedent conditions, e.g.,
food-deprivation,
and variations in behavior, e.g., eating.
This conceptual clarification helped to set psychol-
ogy free to theorize without fear of metaphysics. It
led on to
the use of hypothetical constructs, which did
commit theorists to
postulates about unobservables
usually of a physiological sort. (For this
distinction see
MacCorquodale and Meehl, 1948.) Tolman thus con-
tributed to ridding psychology of the
inductivist myth,
shared by the early behaviorists, that scientists
must
never go beyond what is observed. In fact, however,
the
postulation of unobservables to explain the ob-
served has been one of the most potent sources of
scientific
advance.
In the details of his psychological theory Tolman was
eclectic. He stressed
the importance of both demand
variables and cognitive variables in
behavior, and at-
tempted to state more
precisely assumptions of the sort
which McDougall had incorporated in his
theory of
instincts, i.e., of innate dispositions to pay attention
to
and behave in specific ways towards objects of a
certain class.
In his account of the demand variables Tolman dis-
tinguished first-order drives, which are linked with
specific
antecedent physiological conditions and con-
sequent states of physiological quiescence (e.g., food-
hunger, sex-hunger) from second-order drives (e.g.,
curiosity, constructiveness) which are not so obviously
linked. This
distinction, which was later to become that
between biological and acquired
drives, was important
in the history of behaviorism. On the cognitive
side
Tolman postulated “means-end readinesses”
for
“means-objects” which are innate but docile
relative
to the success of the organism in attaining its goal.
Also in
his account of “behavior supports” he tried
to escape
the sensory atomism of stimulus-response
psychology. He also developed the
concept of the
“sign-Gestalt expectation” to
incorporate the findings
of Gestalt psychology into his assumptions about
the
organism's perceptual field.
Although Tolman emphasized the importance of
innate appetites and aversions
in behavior he was
equally emphatic on the importance of learning, in
which he stressed the role of cognitive variables. He
argued,
also, that the evidence of latent learning was
inconsistent with
Throndike's law of effect. In trial and
error learning a refinement of
sign-Gestalts takes place.
A kind of cognitive map develops of the
different
possibilities as the various alternatives are explored.
Motivational variables are, of course, important in
learning in that they
determine which aspects of a
situation will be emphasized. But learning
depends
primarily on the expectancy of achievement and on
confirmations of the expectancy. In learning animals
and men make
predictions and the maps which they
use to do this are refined more and
more as experience
confirms or falsifies them. As Tolman developed his
theory he became more and more interested in and
convinced of the
importance of cognitive variables. It
is therefore understandable that
behaviorists became
increasingly embarrassed by Tolman's claim that he
was one of them.
