Anatomy refers to the structure of theory, how it is delimited and the components out of which it is constructed. An overview of the variety of the components of theory is presented in Box 1.

Basic Conceptual Components of Theory
Notions
Notions are informal beginnings. They are often provided by imagination, intuition, analogy and metaphor, and can provide material for the development of theory. From the creative side come the juxtapositions, psychotic brainstorms and insights upon which methodological tools may be brought to bear such that conceptual constructs are created and domains constructed. If something is intuitively plausible, then it is likely a notion, as mature theory is often counterintuitive.
Assumptions
Assumptions include postulates, boundary conditions, facts from other theories, and logical relationships between facts. Assumptions are statements about the nature of a domain. These axioms are required before theory can be built. At the start of systematic inquiry, guesswork is often required to choose among seemingly unlimited alternative assumptions. Poorly developed theory can result from leaving assumptions implicit rather than making them explicit. Illumination of implicit or background assumptions can be quite revealing. Longino (1990) discusses the case in which the same body of evidence is said to support conflicting hypotheses or theories, depending upon the investigator's world view or background beliefs and assumptions.
Definitions
Definitions express the essential nature of things. They help specify and convey meanings in definite, clear and determining ways. Among the things that must be defined in a theory are the basic objects and relationships that are the subject matter of that theory.
Concepts
Concepts are generalizations or abstractions of regularities, patterns, and imagined possibilities. They can refer to individuals, phenomena or relationships (Leary 1985) that are explicit enough to be evaluated.
Empirical Content of Theory
Observations
We distinguish between the observations that we make when we are awake and those we make when we are asleep and dreaming. Those observations that we treat as matters-of-fact are open to re-evaluation, their status as facts depend significantly on the ongoing process of renewed observation, or in the case of unique events, checking and contextualizing the record.
Accepted Facts
In human systems the acceptance of facts depends at least in part upon the conceptual environment. Some propositions and the evidence that they are facts may not be accepted, while other propositions with very little or no supporting evidence may be treated as facts. Contrasting viewpoints and critical examination of underlying assumptions are two of the procedures used in the consensual establishment of facts.
Confirmed Generalizations
The abstraction of accumulated records of facts can result in confirmed generalizations. This inductive activity allows a group of observations or facts to become a basic building block for theory, providing material for hypotheses, models and theorems. Contingent on the qualities of the facts, confirmed generalizations are given more credence as supporting evidence accumulates.
Derived Conceptual Components of Theory
Hypotheses
Hypotheses relate conceptual constructs to observable phenomena. They are tentative assumptions and explanations that help formalize expectations and provide grounds for action.
Models
Models are externalized simplified conceptual or mental iconic representations of a system or process, put forward as a basis for theoretical or empirical understanding. Generally they depict some of the overall structure of the system, and those information causality pathways and materials/energy flows that result in the symptoms of interest.
Theorems
Theorems are derived constructs, deduced from assumptions, definitions, basic concepts or the axiomatic structure of models and theories.
Theory Framework and Structure: Theory as System
Framework
A theoretical framework unites all components of theory in a coherent conceptual structure (Figure 8). Relationships between conceptual devices are laid out, including the relations between background assumptions, theoretical constraints and the conceptual inputs and outputs for theoretical models. Frameworks change as theories mature.

Hierarchy
The several potential domains of inquiry of a theory should be related explicitly to each other in a meaningful way. Typically, this occurs by creating a hierarchical organization of (sub)theories varying by scale in time, space and organization. As such, domains are often covered by subtheories, which may be used for different jobs (Pattee 1973) and confer different levels of generality.
Domain
Domains delimit the scope in space, time and level of organization of "a class of phenomena assumed (by theory) to share certain properties and be of a distinct and general type" (Hirschfeld and Gelman 1994:21). The domains of an inquiry should be explicit and specific, as much as possible, though they may be expanded or restricted as theory develops. Domains typically become more and more restricted as theory develops, because refinement shows that the theory is not as grandly applicable as originally presumed.
As mentioned above (under hierarchy), domains may lend themselves to different levels of generality depending on their breadth or their scope. Particularly important for designating a domain are the relevant phenomena, concepts, and scales (time, space, organization). Conceptual constructs in a subtheory domain need not apply to the broader theoretical domain nor to other subtheories, but the importance of determining whether or not they do apply cannot be overstated.
Translation Modes
Translation modes facilitate the conceptual transposition of abstract ideas, generalizations and models to specific domains and on-the-ground applications in experimental or field situations, and back again.
Openness
To maintain a dialogue between abstract or idealized domains and observable phenomena for testing and theory revision, a framework requires translation modes. The space that the translation modes fill is inherently open. Openness in theoretical systems of understanding also is noted where observable phenomena are renamed as facts or confirmed generalizations, inside theoretical frameworks. Openness of theory does not preclude the importance of axiomatic deduction in the development of theory.