NEW YORK AND LONDON
D. APPLETON AND COMPANY
1915
Copyright, 1915, by
D. APPLETON AND COMPANY
Printed in the United States of America
TO MY COLLABORATORS IN THESE RESEARCHES
DANIEL DE LA PAZ
ALFRED T. SHOHL
WADE S. WRIGHT
ARTHUR L. WASHBURN
HENRY LYMAN
LEONARD B. NICE
CHARLES M. GRUBER
HOWARD OSGOOD
HORACE GRAY
WALTER L. MENDENHALL
WITH PLEASANT MEMORIES OF OUR WORK TOGETHER
PREFACE
Fear, rage and pain, and the pangs of hunger are all primitive experiences which human beings share with the lower animals. These experiences are properly classed as among the most powerful that determine the action of men and beasts. A knowledge of the conditions which attend these experiences, therefore, is of general and fundamental importance in the interpretation of behavior.