As a matter of fact, as McDougall himself admits, emotions are seldom experienced in unmixed forms, and it is very difficult to reduce the infinite variety of emotional experiences to any primary forms. One may well agree with James that "subdivisions [in the psychological demarcation of the emotions] are to a great extent either fictitious or unimportant, and ... pretenses to accuracy, a sham." In general, one may say that emotions are closely connected with the native tendencies of human beings and are aroused by both their fulfillment, their conflict, and their frustration. The variety of emotions results from the fact that no single one of our instincts is stimulated at a time, and that the peculiar specific quality of each emotional experience is due to the specific point of conflict, fulfillment, or frustration in each particular case. It may be further noted that those emotions are, in general, pleasantly toned which accompany the fulfillment or the approach to the fulfillment of a native disposition; and those are unpleasantly toned which accompany their frustration or conflict. The depth and intensity of the emotional disturbance seem to depend on the degree and extent to which strong instinctive or habitual impulses have become involved. For as habits of action may be acquired, so also may emotions become associated habitually with them. The emotional disturbances connected with the fulfillment, frustration, and conflict of habits may be just as intense as those connected with similar phenomena in the case of instincts. In one sense these emotional disturbances impede action, certainly action on the reflective level. It is the capacity and function of reflection to solve and adjust precisely those conflicts of competing impulses during which emotional disturbances occur. But the reflective process is confused and distorted in conflicts of native or habitual desires by these emotional disturbances which accompany them. It is proverbially difficult to think straight when angry; the surgeon in performing an operation must not be moved by pity or fear; and love is notoriously blind. The facts with which reflection must deal are presented in distorted and exaggerated form under the stress of competing impulses. Stimuli become loaded with emotional associations. They are glaring and conspicuous on the basis of their emotional urgency rather than on the ground of their logical significance. The paralysis or complete disorganization of action which occurs in extreme cases of hysteria takes place to some extent in all less extreme instances of emotional disturbances.