New Paradigms of Information Age New Age (Integral) Philosophy Foundation Integrity Paradigm


UNIVERSITÉ LAVAL, Department of Physiology

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One shortcoming of the theories of the optimization of behavior proposed by ethologists and behavioral ecologists is that the mechanism, by which behavior is optimized, is never mentioned. In other words, they do not explain how the subject "decides". The main reason for this shortcoming is that there exists some uncertainty whether their predictive models concerned with proximate causation of behavior are functional or mechanistic (Fantino & Abarca, 1985, 1987; Wynne, 1987). <...>

The thesis presented here is that the maximization of pleasure, and the minimization of displeasure, not only leads to useful behavior, but is also the answer to motivational conflicts. It is hypothesized that pleasure serves as the common currency in the tradeoffs between clashing motivations. The displeasure of frustrating one motivation being accepted for the sake of a larger pleasure obtained in satisfying another one. This thesis will be presented step by step starting with the role of pleasure in situations involving only one motivation for a behavior serving only one physiological aim. The second step will be devoted to situations where two motivations clash for behavior that serves physiological aims. In the last step motivations not directly serving physiological aims will be introduced in the experimental conflicts of motivations; thus allowing generalization of the pleasure theory according to which unpleasant and even noxious behaviors may be accomplished because they are traded off for pleasurable rewards.


        Sensory pleasure, one sensory modality at a time

In the commerce of a subject with stimuli, it has been shown experimentally that the wisdom of the body leads the organism to seek pleasure and avoid displeasure, and thus achieve behaviors which are beneficial to the subject's physiology (Cabanac, 1971). Relations exist between pleasure and usefulness and between displeasure and harm or danger. <...>


        Maximization of bi-dimensional pleasure: The hypothesis


        Maximization of bi-dimensional sensory pleasure: The evidence, human behavior.


    Optimal behavior

The word optimality applied to behavior can be ambiguous because it bears somewhat different meanings when used by Ethologists, Economists, or Physiologists (Lea et al., 1987). Ethologists differentiate between goal and cost. Economists differentiate between utility and cost. <...>

To the Physiologist a behavior is optimal when it leads to homeostasis. <...>


    The common currency

The experiments reported above were limited to sensory pleasure and to conflicts of motivations with clear physiological implications. One may question whether it is possible to extend the conclusions to other domains than biology. The notion of behavioral common path is especially enlightening to answer that question. Paraphrasing Sherrington's image of the motoneuron final common path of all motor responses, McFarland & Sibly (1975) pointed out that behavior is also a final common path on which all motivations converge. This image incorporates all motivations into a unique category since behavior must satisfy not only physiological needs but also social, moral, :sthetical, playful motivations. Indeed, it is often the case that behaviors are mutually exclusive; one cannot work and sleep at the same time. Therefore, the brain, responsible for the behavioral response, must rank priorities and determine tradeoffs in the decisions concerned with allocating time among competing behaviors. It can be expected that the brain operates this ranking by using a common currency (McFarland & Sibly, 1975; McNamara & Houston, 1986). The metaphor of the common currency was used by McFarland and Sibly (1975) because:

"the necessity for comparing the merits of different courses of action [implies] that there must be some trade-off mechanism built into the motivational control system. Since the trade-off process must take into account all relevant motivational variables, it is clear that the mechanism responsible must be located at a point of convergence in the motivational organization" (McFarland & Sibly, 1975).
The results of the above experiments show that sensory pleasure fulfilled the conditions required of a common motivational currency, at least in the case of the behaviors selected which have clear physiological implications. Pleasure permitted ranking thermal comfort above fatigue, or conversely. If it can be accepted that, at each instant, a subject responds in the realm of physiology to the motivation that will provide the greatest additional sensory pleasure for any given cost, because there is a need for a common currency, we may conclude that pleasure is also the common currency for non-physiological motivations. In the experiments described below cold discomfort or the relief from pain, was pitted against money or teh pleasure of a videogame. In these conflicts the subjects used pleasure as the common currency in the respective trade-offs.

    Money and playful behavior



    Pleasure and behavior

The relation of pleasure to behavior was regarded as obvious by the Greek philosophers Aristotle (284-322, B.C.) and Epicurus (241-170, B.C.,see Conche, 1977):

"Life and pleasure, as we can see now, are not separable; for without behavior there is no pleasure, and pleasure improves behavior." (Aristotle)
After the Greeks, many philosophers and thinkers such as St Augustine (354-430, see Lamarre, 1986), St Thomas Aquinas (1224-1274), Montaigne (1533-1592, ses Saulnier, 1988), Gassendi (1592-1655, see Bloch, 1971), or Sulzer (1751) recognized in the affective experience a great role, if not the essential role, as a motivation. Bentham (1742-1832, see Bowring,1838) based his "greatest happiness principle" on pleasure, "the spring of action". Kant (1788, see Picavet, 1983) and Mill (1863) were more concise but equally clear on this point. For Freud (1920) the "pleasure principle" determines the aim of life. An important analysis of the role of the affective process in behavior has been carried out by Duncker (1940-1):
"A search for the ultimate motives of human conduct cannot disregard pleasure which many eminent minds have considered to be the fundamental motive, or at least an important one. Others, to be sure, have held that pleasure is the outcome rather than the motive or goal of human striving... There cannot be the slightest doubt that many human strivings bear some kind of reference to pleasure, and likewise that many pleasures bear some reference to striving".

Yet pleasure has never been popular in history for moral reasons. In addition the excesses of psychoanalysis have led to the rejection of all mentalistic explanations of behavior. As a result pleasure is shunned by most recent textbooks, a drawback of behaviorism in modern literature. <...>

One good reason for the rejection of pleasure from the realm of science was the lack of experimental evidence and the fact that the philosophers conclusions were based on their own introspection only. This rejection may be based on earlier approaches to these phenomena but,

"as new techniques are developed, our ideas often have to be revised to encompass the new information obtained" (Teitelbaum, 1964).

    Animal behavior


Maximization of pleasure may thus be the link between physiology and behavior and give the key to the problem of physiological optimization without the implication of the animal's knowledge and rationality about its physiological state. A working man does not have to know his body temperature, blood oxygen and glucose, muscle glycogen and lactic acid, etc to take an occasional but necessary break. He just has to "listen to" his sensations and maximize the algebraic sum of pleasures, a summation that is hardly conscious. By using the same mechanism animals also can make the right decisions. The seeking of pleasure is sufficient to actuate an appropriate behavior. This central place of pleasure in animal behavior is now being postulated when interpreting experimental results (Waldbillig & O'Callaghan, 1980; Baldwin, 1985; Mehiel & Bolles, 1988; B_dard & Weingarten 1989) and field observation (Hladik, 1977), or plainly recognized from theoretical considerations (Bindra, 1978; Lester, 1984; Toates, 1986).



    Apparent contradictions

Complex situations with more than one stimulus at a time, seem frequently not to follow the rule:

pleasant = useful,

and are often taken into consideration to refute that rule. Five cases can be listed where the search for pleasure does not seem to result in useful behavior.


    Pleasure at the crossroads

"How can you compare the pleasure of cheese and beer with the pleasure of seeing a good Hamlet?" (Ladd, 1894).
The question raised at the beginning of this essay was to understand how subjects make their decisions. At the end of the essay one might ask whether anything is new from what was known to Epicurus, Gassendi, Bentham, and Mill. The experimental approach summarized in the above pages answers this question and provides two advantages. First, reproducibility and the sharing of evidence means that we can extend the discussion beyond the domain of morals to that of science. We can apply rigor to an area of knowledge that was previously based only on intuition and common-sense. Second, the experiments are at the crossroads of Biology, Psychology, and Economics and contribute to bring these sciences together.


As a general conclusion, it is proposed that animals and humans rank priorities in choice situations and thus optimize their behavior by the amount of pleasure aroused by this behavior. As an economist wrote:

"Pleasures and pains represent the sole genuine basis for understanding human motives" (Jevons, 1871).
Bentham's fourteen tables of the springs of action, and Duncker's four causes of pleasure can be compared to one another for the very good reason that present or expected pleasure is the common currency to past, present, and future actions. The "law of effect" would act, not as a learning process only, but also as a way for living organisms "to know" that they are producing an optimal behavior. At the same time pleasure renders unnecessary high levels of rationality in the process of decision making. Indeed it has been recognized that rationality plays only a modest part in the determination of behavior (Cooper, 1987). In situations of conflicting motivations, pleasure would serve as a common currency, with additive properties, for the ranking of priorities and the resulting tradeoffs. The great advantage of pleasure both as a motivation and as a key to optimization lies in its versatility. Pleasure renders unnecessary the multiplication of instinctual rigid stimulus-response programs and stimulus-bound reflexes (see Epstein, 1982) whose number would have to increase ad infinitum with the complexity of living organisms2. S-R programs could not provide the flexibility which characterizes most of the purposive, goal-directed behavior of more advanced animals. Pleasure opens an infinite register of new responses. Indeed it is far more simple to maximize pleasure than to accumulate within the CNS an infinite number of instinctual responses. Pleasure in this case is analogous to the multiplicative function programmed in a calculator. It is far more simple to have access to that function than to store the infinite number of possible multiplications of rational numbers.
Human liberty is often ill understood as the freedom to do everything. Actually it is to be understood as the freedom to choose one's own way to maximize pleasure. Among the motivations sorted by Sulzer (1751) as sensory, intellectual, and moral, the latter has always been considered by the philosophers as the most rewarding.


<Very long and useful list of references.>