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PREFACE.


The appearance of the HARVARD PSYCHOLOGICAL STUDIES does not indicate
an internal change in the work of the Harvard Psychological
Laboratory. But while up to this time the results of our
investigations have been scattered in various places, and have often
remained unpublished through lack of space, henceforth, we hope to
have in these STUDIES the opportunity to publish the researches of the
Harvard Laboratory more fully and in one place. Only contributions
from members of the Harvard Psychological Laboratory will be printed
in these volumes, which will appear at irregular intervals, and the
contributions will represent only our experimental work;
non-experimental papers will form an exception, as with the present
volume, wherein only the last one of the sixteen papers belongs to
theoretical psychology.

This first volume does not give account of all sides of our laboratory
work. An essential part of the investigations every year has been the
study of the active processes, such as attention, apperception, and
volition. During the last year several papers from these fields have
been completed, but we were unable to include them in this volume on
account of the space limits; they are kept back for the second volume,
in which accordingly the essays on the active functions will prevail,
as those on perception, memory, and feeling prevail in this volume. It