that operational localization of such effects can be demon-
strated. Finally, the Olds and Milner article is included
as a recent break with the methods of the past which
has the effect of suggesting new ways to talk about the
problem of response consequence effects on response
acquisition. Miller's summary refers to the wide body of
research on the learning process and traces the utility and
shortcomings of the "reduction" definition of the law of
effect.

Earlier mention was made of the work of the asso-
ciationists in the field of learning research. These work-
ers, beginning with Pavlov and represented through the
years by Guthrie and Skinner, also use the term rein-
forcement but do so in a descriptive way devoid of further
implication of effect on the organism. By refusing to
consider this possibility they have been free to concen-
trate on systematic exploration of certain situational
parameters as they affect response acquisition. It was our
feeling that these studies lay outside the scope of this
volume; perhaps a separate volume for them is justified.

It seems quite likely that a topic such as reinforcement
has been sufficiently overworked to produce considerable
disagreement about which studies are the most important.
Judging from the tenor of many of the articles consid-
ered for this book, it is a certainty that far more partisan
selections might have been made for one disposition or
another. However, this volume attempts to keep the
uncommitted reader in mind, and assumes that he is
quite capable of pursuing any topic that stimulates him
to seek additional materials.

-viii-