Excerpt from Enterprise Architecture Fundamentals:
Tasked with mapping enterprises’ territories, the architect’s learning curve starts with a menacing swerve that may lead rookies astray with little chance of getting back on track. Hazards come from a series of potential mix-ups. At the outset, because territories have to be documented one way or another, preliminary outlines and depictions can easily be confused with maps. Hence, initial descriptions of objects and phenomena in environments (figure 2-3, left) should be set apart from their systems’ representations (figure 2-3, right).
Figure 2-3. A 3D Perspective: Physical, business, Representations
Compounding the difficulty, modellers have to differentiate between items that are physical (e.g., Bob’s car) and those that are symbolic (e.g., the model of Bob’s car as marketed by vendors), while working on morphing territories’ elements into map- ping categories. Physical items are set in territories (figure 2-3, bottom left), whereas symbolic ones are seemingly placed somewhere in no-man’s-land (figure 2-3, top left).
Confusion can be avoided by distinguishing between symbolic objects and sym- bolic representations. Symbolic objects are intangible entities defined by social un- derstanding, whether institutional or customary (e.g., contract, music). By contrast, symbolic representations are digital (or clay, or quantum) depictions (e.g., car main- tenance record, music sheet) that mirror the state of external entities, which can be tangible (e.g., actual cars) or intangible (e.g., car registration, song). These sym- bolic substitutes (or surrogates) constitute the raison d’être of information systems; they serve as the symbolic counterparts of external objects or phenomena, which are meant to be managed through supporting systems:
• Physical: containers, persons, active objects (i.e., possible source of events), pas- sive objects, noncountable (NC) objects, events, processes
• Symbolic: containers (e.g., a team), collective agents (e.g., organizational units), objects, roles, activities, partitions (or powertypes2)
Figure 2-4. Modeling 101
Those actual and symbolic categories are then combined using a compact set of unambiguous syntactic constructs shared by modeling languages.