The normal range of reaction in response to any of our stimulus words is largely confined within narrow limits. The frequency tables compiled from test records given by one thousand normal subjects comprise over ninety per cent of the normal range in the average case. 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 pr{\ae}cox, some paranoic conditions, manic-depressive insanity, general paresis, and epileptic dementia the test reveals some characteristic, though not pathognomonic, associational tendencies.