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PROBLEMS OF CONSTANCY AND CHANGE IN NEEDS
Lane Tracy
Department of Management Systems
Copeland Hall
Ohio University
Athens, OH 45701
Key words: need, purpose, resource, lack, excess, stability, change, living systems
ABSTRACT
Several theories treat needs as relatively stable attributes of human individuals. Yet needs are characteristic of all living systems and the apparent stability of needs is an artifact of aggregation. That is, needs are grouped into categories such that, although the existence or intensity of specific needs may change, the overall level of need within the category appears relatively constant. In addition, some resources are consumed or lost and replenished so rapidly that the need appears to be constant because of aggregation over time.
A need of a living system may be defined as "lack of a specific resource which is useful for or required by the purposes of that system" [5]. From that point of view needs must change in intensity as a function of the system's hierarchy of values and the degree of lack. A system may act to maintain a constant low (or null) level of lack, but its ability to do so depends partly on whether it can store the resource in anticipation of need or develop means for steady replenishment.
Theories of human need tend to treat needs as being relatively stable. Maslow [2], for instance, indicates that, although a specific need may be satisfied at any given moment, the prepotency of the need remains constant. Furthermore, Maslow asserts that most human needs fall into five hierarchical categories and that, for any individual, the needs in one of these categories tend to be dominant for long periods of time. Alderfer [1] recasts needs into three categories, but maintains the same tendency for stable dominance of one category of needs. McClelland [3] believes that people demonstrate a stable, learned pattern of dominance among needs for achievement, affiliation, and power.
Tracy [5] has criticized these and other current theories of human needs on the grounds that:
1. Stability of needs is assumed;
2. The need concept is not well defined;
3. Descriptions of needs and need categories are ambiguous;
4. Lists and categories of needs are incomplete;
5. Agreement on a list of basic human needs is lacking; and
6. The theories are limited to human needs, even though the concept of need applies to living systems in general.
The assumed constancy of human needs is the basis for bodies of literature concerned with identifying these needs for purposes of relieving deficiencies, equalizing distribution of needed resources, and motivating work performance. Yet there are reasons to believe that the apparent constancy of needs is an artifact of inadequate definition and ambiguous categorization.
A Living Systems Definition of Need
Tracy proposed a definition of need as follows: "A need of a living system is a lack of a specific resource which is useful for or required by the purposes of that system" [5, p. 212]. This definition rests on the living systems concept of purpose. According to Miller [4], a living system has a variety of Purposes, which are preferred internal steady-state values. The system acts purposefully to maintain or reattain these steady states.
Preferred steady state values of a living system relate to its broad tendencies to (1) maintain itself in a state of health, (2) actualize its potential through growth and development, and (3) Propagate itself through reproduction or dissemination. These broad tendencies establish a hierarchy of the purposes associated with them, inasmuch as good health is generally necessary for growth and development to occur, and development is necessary before the system can reproduce or disseminate.
Some purposes are established by the template of the system and subj natively immutable, but other purposes are learned and to change in response to environmental stimuli. As purposes change, so do needs. A need may be created by the raising of a purpose (e.g. increasing aspiration for knowledge) and may be reduced or eliminated by the lowering of a purpose (e.g. deciding that one child is enough).
Needs also change because of inputs, outputs, and processes of the system. Living systems are constantly consuming and outputting resources. Maintenance of steady states requires that a system take action to obtain new resources and to conserve what it has. Thus, a state of need may occur or increase in degree because the rate of input is too low, the rate of consumption or outflow is too high, or the purpose value increases.
An excess of a resource has much the same effect as a lack. In either case there is a departure from the purpose of the system, and the system is motivated ‘to act in order to return to the purpose value. Thus, for each resource there is a continuum centered on its purpose value, as shown in Figure 1.
Figure 1. Relationship of purpose, lack, and excess [5].
Changing Needs
How may needs change? According to Tracy's definition and model, a given need may vary in both existence and degree.
Above the level of requirement no need exists; below that level the need increases in degree of intensity as the resource departs further from its purpose.
A change in the flow of an input or output or in the rate of consumption of a resource may cause a condition of need or excess. For example, plunging into cold water would cause a sudden loss of oxygen and heat, creating in a person a strong need for these resources. Heavy work or exercise would stimulate needs for rest, liquids, and food energy.
Likewise, a need may be created by information that causes a change in a purpose or its place in the hierarchy of purposes. A weather report predicting a cold:front may cause a change in a person's preferred value for skin temperature or it may put that value higher in the hierarchy of values, thereby making it more likely to be acted upon.
Needs may also vary with respect to their power to evoke behavior. Although this power is obviously related to intensity, it is also determined in part by the intrinsic importance of the need. Some needs are more vital than others; some needs are urgent while attention to others can be postponed almost indefinitely; there are many substitutes for some needs, none for others. The system's hierarchy of values determines the intrinsic importance of each need.
At any given moment a system may have many needs, not all of which can be acted upon at once. The system must select which needs will receive attention first. The system's hierarchy of values serves as one determinant for the choice, and the intensity of each need is another. The system must somehow combine these determinants so as to compare a need of high value to the system (intrinsic importance) but low intensity with one of low value but high intensity.
It appears that, although the importance of specific needs may be rather constant, they must change quite frequently in intensity and, therefore, in their power to command attention.
The assumption of stability makes sense only if needs are aggregated over time, grouped into categories, or equated with the resources that fulfill them. All of these ways of treating needs are flawed, however.
Aggregation over time. Some resources are consumed rapidly or lost easily through output or deterioration. The need for such resources recurs frequently unless a steady input is maintained or the system is able to store large amounts. An example is oxygen, which is consumed vapidly by the human body, and for which there is little storage capacity. An actual lack of oxygen seldom occurs because the mechanism for replenishing the supply is well established, but if the supply were cut off the need would quickly become acute.
Other resources can be stored readily or are consumed or lost very slowly. Certain minerals, for example, are stored in the human body for long periods and consumed very slowly or not at all because they act as catalysts. As with oxygen, a lack seldom occurs. A lack of most minerals would not be considered acute, but in the long run might be as fatal as a lack of oxygen.
How are we to compare the needs for oxygen and minerals? Using time as a criterion, we could say that the need for oxygen is dominant because failure to meet the need will more quickly result in illness of the system. If we view the situation over a sufficiently long period, however, a person may be more likely to suffer a lack of minerals than a lack of oxygen. The reason is that viable systems tend to establish a regular means for fulfilling critical needs. To take an example from another level of living systems, most hospitals maintain an auxiliary supply of electrical power to be used in the event of a power outage. The complex systems of electrical monitors and machines used in health care today require that a need for power not occur.
To sum up, over time the need for any resource is a function of rate of consumption or loss, storage capacity of the system, and the existence of structures for maintaining a steady flow of input or substitution. It means little to say that a need for something tends to persist or recur over time unless we know why it persists or recurs.
Aggregation into categories. Grouping needs into categories makes even less sense than aggregation over time. Oxygen, minerals, food, and water all fall within Maslow's [2] category of physiological needs, for instance, but they vary widely in terms of the likelihood of a lack. Needs for food and water are considered to be highly prepotent because the likelihood of a lack is high and/or the consequences of continued lack for the health of the system are great. But do oxygen and minerals share this high prepotency? The consequences of lack of oxygen are severe, but the likelihood is low. In the short run a lack of minerals is neither very likely nor very critical to health.
The likelihood of a need for food and water is based on rapid consumption (but not as rapid as for oxygen or as slow as for minerals), limited storage capacity (but not as limited as for oxygen or as available as for many minerals), and arrangements for replenishing the supply, which are subject to a variety of variables but tend to be less certain than for oxygen. By aggregating such dissimilar needs into one category we obscure the factors that determine the importance of each need.
A further problem with categories of needs is that they vary in breadth. What does it mean to say that physiological needs are prepotent over ‘safety needs, or that Relatedness needs must be satisfied before Growth needs can become dominant, if the sizes of the categories are different. The dominance of physiological or Relatedness needs might reflect nothing more than the fact that such needs are more numerous than those in the higher categories. Unless there is some clear principle involved in the dominance of one category over another, the whole concept of a need hierarchy is meaningless. As we have just seen, there seems to be not just one principle, but a complex set of interacting factors that determine the potency of any need.
Equating needs with resources. As our own stomachs tell us, the need for food is not constant. Lack of food recurs cyclically because consumption is relatively constant while replenishment of supply is periodic rather than continuous. Nevertheless, if we say that food is a human need, it appears that the need is constant.
Carbohydrates and other components of food are requirements for human health and growth. Equating the need with the resource that fulfills it obscures the need concept in at least two ways, however. First, it ignores the open-systems basis of the concept. Needs exist because living systems are dependent on the environment for resources to replace those that are consumed or lost. The concept doesn't apply to closed systems. We don't say that a rock needs mineral matter. A rock requires minerals but doesn't need them because it is never without them.
Second, a given need often may be fulfilled by more than one resource. The human body needs nourishment from time to time, but. there is a wide variety of foods that will fit the bill.
No particular kind of food is required. Indeed, nourishment could be supplied intravenously or through drink, thereby eliminating the "need" for food altogether.
Prepotency
If needs themselves are not constant, there remains the possibility that their "prepotency" or tendency to be acted upon may be. Some needs are prerequisite to others. A system is more likely to attend to a need that threatens its existence than one that retards growth. Likewise, a need that threatens development of the system would probably be acted upon before one that inhibits propagation. This might be called the rule of primacy.
Another variable that may influence the long-term tendency to act on a need is urgency. That is, some needs grow more rapidly and/or recur more frequently than others. If not attended to quickly, such needs become intense. Needs for resources that are consumed rapidly and for which there is little storage and no substitute are of this nature. We could Say, for instance, that the human need for oxygen is more urgent than for water, which in turn is more urgent than the need for nourishment, which is more urgent than the need for calcium.
Normal frequency of occurrence of a lack may also affect Prepotency. We could say that the need for human labor in a business organization is prepotent over the need for electrical eee because there is frequently a shortage of labor but iepen a lack of power. Frequency of occurrence interacts with urgency and primacy, however. For resources that are of high importance or urgency systems usually develop storage capacity or a ready supply, so that a lack seldom occurs.
Unfortunately, there is no clear way to combine these notions of prepotency. The basic minimum needs for oxygen, water, nourishment, and calcium are equally prerequisite to needs engendered by growth or reproduction but differ greatly in urgency and frequency. For a student pursuing a degree, on the other hand, knowledge may assume prepotency over most | physiological needs, particularly when an examination is at hand.
The basis of Maslow's [2] concept of prepotency is ill-defined, but it seems to be based upon primacy. In general, physiological and safety needs are concerned with maintenance of human health, and thus are prerequisite to love and belongingness needs. These in turn are developmentally prerequisite to esteem and self-actualization. With respect to urgency and frequency of lack, however, the needs in each category vary greatly, making it difficult to predict whether a given need is likely to be dominant.
Summary
It would be convenient if the needs of living systems were relatively stable. We could then predict behavior with a reasonable degree of confidence. But needs, when properly defined, appear to be quite changeable. They may be stable with respect to primacy, urgency, and frequency of occurrence, but they vary greatly in intensity. The tendency or power to evoke behavior is a function of all of these factors, and is therefore not constant. Aggregation of needs may produce an appearance of greater constancy, but it also obscures the basis of need. Change is part of the very nature of needs.
REFERENCES
1. Alderfer, C.P. (1972) Existence, Relatedness, and Growth. New York: Free Press.
2. Maslow, A.H. (1970) Motivation and Personality, 2nd ed. New York: Harper & Row.
3. McClelland, D.C. (1961) The Achieving Society. Princeton, NJ: Van Nostrand.
4. Miller, J.G. (1978) Living Systems. New York: McGraw-Hill.
5. Tracy, L. (1986) Toward an improved need theory: In response to legitimate criticism. Behavioral Science, 31, 205-218.
