Organisms want to survive. They have a variety of biological needs like eating and sleeping. They also strive after mating and reproduction in order to preserve their genetic information. Their behavior is structured around biological rhythms, habits, moods, daily paths through time and space, handling impulses. There is no global rationality; there are only local needs, local perceptions, local actions (principle of localization).
Development
Cells are created by cell division. Later they grow and adapt. Organisms are created by sexual procreation. They grow by cell division, and adapt to the circumstances in their environment. The coherence of an organism is based on gene-directed growth. They learn habits. Individuals can be seen as bearers of genes and memes. Memes are packages of cultural information, sign complexes.
“Examples of memes are tunes, ideas, catch-phrases, clothes fashions, and ways of making pots or building arches.” (Dawkins, office space, 1976/ 1989: 192).
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Genes and memes strive after survival, and strive to spread themselves over the world. Species adapt by mutation and selection (biological evolution).
3.2. The information system as a cell or organism
The behavior and structure of cell metaphor information systems
An information system as a cell is characterized by its fluent and adequate interaction with people. The information system consists of objects that take care of preserving their own integrity and that react on events. The cell metaphor is characterized by interaction and integrity. If we see an organization as an organism, an information system is a specialized cell or organ. An information system encapsulates itself within a kind of cell wall, thus maintaining its own integrity. An information system consists of smaller bodies (objects) with a specialized function, of which the bearer of inherited, type-determining information is the most noticeable. An information system can also be seen as a larger cluster of cells (objects), of which each cell maintains its own integrity, while these cells communicate by sending and receiving messages through their cell walls. Communication is regulated by the cell wall encapsulating private material and behaving according to its structure, only permitting access to recognized material. An information system is grown, not built. Grown above a certain size, an information system tends to divide itself or to disintegrate. Information systems have a limited lifetime, but their type-determining information may be copied by new information systems. Information systems need information (food) to grow and to live, and can process raw material into food for themselves and other components of the organism.
Object-oriented analysis, design, and programming
The cell metaphor finds its computer science foundation in the object concept. Several aspects of this cell metaphor can be recognized in the object-oriented analysis, design and programming paradigm (Goldberg and Robson, 1983; Coad and Yourdon, 1991a; 1991b). This paradigm also contains principles –such as simulating the real world by a world model—that fit into the mind metaphor. An object is a virtual entity realized on a running computer system. An information system can be described as a system of objects serving an organization module. A cell is represented by either an object or an information system. An object has a life cycle, a behavior determined by methods, and a memory based on private data. The encapsulation and message passing principles are obvious. In object-oriented information systems, integrity maintenance is more natural than in imperatively built information systems. The class as a kernel containing the inherited type-determining information is apparent. The principle of reusing information systems by copying its class definitions and altering them is well known.
Locality
An important aspect of information systems seen as cell clusters, in which the cells are the objects, is that the activity of the information system in fact consists of the object activities, and that these object activities are purely local in this sense that an object only can execute its inherited methods, and only can process material which is available within the object.
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Growing information systems
The objectives of the cell metaphor information system are first and foremost the survival of the organization, and secondly the survival of the information system during its natural life cycle. The development of information systems is primarily seen as an evolutionary process, in which competition between information systems and incremental change play roles.
The principle of growing is recognizable because object-oriented systems are grown by feeding them -as running symbol systems- with information.
“When my program is running, I am typing in some new statements, and then he is actually eating it and growing by it.” (Wouter Gazendam, Virtual Office: 11 years old, 1990).
According to the cell metaphor, information systems must be grown. There is empirical evidence for the success of such an approach (De Jong and Gazendam, 1991:
“Group by group tasks have been computerized using microcomputers. Most computerized systems were database applications that could be realized in a short period of time using a fourth generation language; a result with which the users were pleased. These modular systems, developed according to the zoning plan, were disseminated throughout the whole organization, where they were subsequently incrementally changed and used… the developed systems were step by step integrated…leading to a decrease in the abundant streams of forms… one of the consequences was the possibility to work client-oriented… There is empirical evidence that the zoning plan approach is substantially more efficient than the blueprint approach . . .”
Genetic algorithms (Holland, Holyoak, Nisbett, and Thagard, 1986; Goldberg 1989) can be used for creating descendant objects from parent objects, and provides also selection mechanisms for the survival of the fittest. Artificial life consists of very simple beings that develop and reproduce in a virtual environment (Holland, 1995; Ward, 1999).
The methodology of planning, designing, and developing object-oriented information systems has developed rapidly in the last decennium. Experiences have been documented as patterns (Gamma, Helm, Johnson, and Vlissides, 1995; Fowler, 1997; D’Souza and Wills, 1999). A universal language for analysis and design, UML, has been developed (Rumbaugh, Jacobson, and Booch, 1999; Booch, Rumbaugh, and Jacobson, 1999; Jacobson, Booch, and Rumbaugh, 1999).

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