J. B. Watson was by no means the first to see the
importance for psychology
of the objective study of
behavior. William McDougall, in his Physiological
Psychology in 1905, had defined
psychology as “the
positive science of the conduct of living
creatures” and
had resisted the tendency to describe it as the
science
of experience or of consciousness. In 1908, in his Intro-
duction to Social
Psychology, he explicitly introduced
the term
“behavior” claiming that psychology was
“the
positive science of conduct or behavior.” He
main-
tained that psychology must not
regard introspective
description of the stream of consciousness as its
whole
task. This had to be supplemented by comparative and
physiological psychology relying largely on objective
methods, the
observation of man and animals under
all possible conditions of health and
disease. Similarly
in 1911 W. B. Pillsbury, a pupil of Titchener,
published
his Essentials of Psychology in which he
claimed that
psychology should be defined as “the science of
human
behavior.” But neither McDougall nor Pillsbury put
forward a puritanical or restrictive position. They were
merely arguing
that the objective study of animals and
of physiology had a lot to
contribute to psychology.
It was therefore unwarranted to give a definition
of
psychology which excluded their findings from the
outset.
What was distinctive about Watson's view of psy-
chology was what it excluded rather than what it
included; for
McDougall himself was a devotee both
of physiology and of animal studies.
Watson was deter-
mined to rule out
introspection as a legitimate method
of obtaining data and to banish
“consciousness” and
other mentalistic terms from the
conceptual scheme
of his new science. What led him to this methodolog-
ical puritanism?