It will be perceived that the scheme of the nature of purposes, which we have outlined, conform in certain ways to the usual teleological account. Purpose represents, and, in a sense, possesses, an "end." This "end" is the terminal phase of the emotional or action experience, assuming it to be "successful." This terminal phase is vaguely represented by the "desideratum image." However, it is evidently a mere confusion of meanings to say that the "end" is present in the beginning, or controls the process. What is present is merely an imperfect symbolization of the "end," and since the latter is non-existent it can have no bearing upon the situation. Nevertheless, we might state correctly that the desideratum image has been determined by the "end" or terminal phase of a previous experience of the same general sort, or by some more complex but equivalent biographical factor. While there seems to be no scientific sense in the notion that the "end" determines the process, it is easy to see how such confusion of thought can arise with reference to such a psychological process as that which we have considered: since the purpose is itself a "thought," taking the "end" as its meaning. It is therefore subject to the usual "stimulus error," which substitutes meaning for actual mental content. So far as the operations of purpose can be observed introspectively, they follow the normal formula of efficient causation. The desideratum image appears to regulate the associative and volitional processes as if it were a present determining agency. There seems to be no reason for denying the reality of this effectiveness, so long as we confine ourselves strictly to the psychological domain, and also no excuse for distorting it into the fantastic scheme of "final causation."
The apparent causal efficacy of purpose in the mental domain is attributable to its correlation with conditioners of retroflex action. We have seen that retroflexes act as controlling agents, inhibiting or facilitating forms of response in accordance with their bearing upon the continuation of the given retroflex processes. Purposes appear to act in much the same manner on the mental side of the psychophysical system, enhancing or repressing ideas and volitional tendencies in accordance with their abilities to subserve the purposes in question. The exact relationship between purpose and retroflexes depends, however, upon whether the latter are negative or positive. Primitive inexperienced desire, involving the direct arousal of a retroflex process, is associated with negative retroflexes only. On the psychological side, in this case, there is no representation of the object of the desire. Purpose and typical desire are only possible when retroflexes have been conditioned, and associations have been established through experience.
In the case of a positive retroflex, the purpose or desideratum image may be regarded as the psychical parallel of the conditioning sensory pattern. Thus, the sight of food arouses a desire to eat it. Both the appearance of the food and the representation of the act of eating have been associated with pleasant gustatory and olfactory sensations, which correspond to the direct excitants of the positive retroflexes. The purpose in this instance may conceivably consist in representation of the "taste" of the food, or it may be composed of kinaesthetic imagery, standing for the acts of ingestion. In sexual desire, the purpose may represent the sensations of the orgasm, or some associated perceptions, such as those of contact with a person of the opposite sex. In these examples, the relationship with the retroflex or pleasurable sensations is so direct that there is no difficulty in recognizing the principles which are involved. If, however, we consider a case such as that which is presented by a man who is walking down the street with the idea in mind of purchasing a new suit of clothes, the connection with retroflexes is somewhat more obscure. However, it is our belief that the image representing such a purchase is actually correlated with neurograms which have been facilitated in a retroflex manner. New clothes aid a man's standing in the community and assist him in earning his bread and butter, as well as protecting him from cold. In the case of a woman, they have a very direct relationship to success in the sexual sphere.
The direct conditioner of a negative retroflex cannot be represented by a positive purpose in consciousness, since such a conditioner sets up processes which tend to eliminate it from the situation. In the case of a negative retroflex, the purpose corresponds to the pattern of the elimination. If we wish, we can say that the conditioner of a negative retroflex corresponds with a negative purpose, or a mental representation which tends to be repressed, the related positive purpose embodying its contrary. In general, the purpose in such cases will correspond to the least inhibited of all of the forms of response which have previously been concurrent with the operation of the negative retroflex in question. If the individual was successful in eliminating the unpleasant sensations, the least inhibited response will naturally be the one which accompanied such elimination. It is highly probable that this response will not only fail to be strongly inhibited, but will actually be facilitated. This latter effect may be attributed to several conceivable processes: firstly, rebound effects accompanying the release of the inhibition (analogous to what Sherrington calls successive spinal induction); or, secondly, the possibility which we have already suggested, that a decrease of nociception acts beneceptively. A third possibility enters when the given type of escape has been effected or imaged more than once, and lies in the reinforcement of the desideratum pattern by the nerve currents corresponding to actual perception. At any rate, we observe that the final stage in a successful negative emotion is positively pleasant.
Advanced human purposes are ordinarily founded simultaneously upon a number of retroflex conditioners, or their negitions. Thus, the very prevalent purpose among men of making money, represents a condition for the arousal of all positive retroflexes and also for the avoidance of all negative ones. It is obvious, on the psychological side, that purposes can be arranged into a hierarchy in which one purpose is subservient to another. The purpose to earn money is subservient to that of obtaining food, of obtaining clothing, of securing a sexual mate, and innumerable other purposes which may be entertained separately. Many of the latter, however, can also be regarded as subsidiary. Thus, obtaining food is instrumental to avoiding hunger and gaining the pleasures of eating. Winning a mate is instrumental to erotic gratification. Our thesis must evidently be that the majority of purposes, no matter how advanced, are ultimately subservient to the avoidance of the basic unpleasant sensations and the acquisition of the pleasant ones. This hierarchical arrangement of purposes will be paralleled on the physiological side by the relationships between primary, secondary, tertiary, and higher orders of retroflex conditioning. There are some reservations, with regard to the rule that all purposes ultimately reduce to instruments of the pleasure-displeasure senses, which are due to the action of the principles of exercise and decay. Nevertheless we can assert correctly that all purposes are based ultimately upon the establishment of pleasant experiences or the removal of unpleasant ones. It should be noted that this statement is not equivalent to the usual hedonistic formula according to which the purpose explicitly represents the pleasantness or escape from unpleasantness as an end. It merely asserts that prior affective experience is in fact the actual determinant of the existence of the purposes, whatever their present content may be.