With the aid of the frequency tables and the appendix normal reactions, with a very few exceptions, can be sharply distinguished from pathological ones.
The separation of pathological reactions from normal ones simplifies the task of their analysis, and makes possible the application of a classification based on objective criteria.
By the application of the association test, according to the method here proposed, no sharp distinction can be drawn between mental health and mental disease; a large collection of material shows a gradual and not an abrupt transition from the normal state to pathological states.
In dementia præcox, some paranoic conditions, manic-depressive insanity, general paresis, and epileptic dementia the test reveals some characteristic, though not pathognomonic, associational tendencies.
ACKNOWLEDGMENTS.
It is with pleasure that we acknowledge our indebtedness to the many persons who have assisted us in collecting the data for this work.
About two hundred tests upon normal subjects were made for us by the following persons: Dr. Frederic Lyman Wells, Dr. Jennie A. Dean, Miss Lillian Rosanoff, and Miss Madeleine Wehle.
Dr. O. M. Dewing, the late superintendent of the Long Island State Hospital, and Dr. Chas. W. Pilgrim, superintendent of the Hudson River State Hospital, have assisted the work by kindly permitting the test to be made upon employees of these institutions, and we are especially indebted to Dr. F. W. Parsons for personal assistance in securing the co-operation of many subjects.
Professor R. S. Woodworth, of Columbia University, extended to us the courtesy of the Psychological Laboratory during several weeks of the summer session of 1909, and gave us much assistance in obtaining interviews with students; we received assistance also from several of the instructors of Teachers' College, especially Mr. Wm. H. Noyes.
We are indebted to Mr. F.C. Lewis and Mr. W.E. Stark, of the Ethical Culture School, New York, for permitting us to make the test upon the pupils of that school.