Key Vocabulary: Model

           We use a specific meaning of model whenever we use the term in epi-thinking.  The meaning is derived from Robert Rosen's modeling relation.

           The Modeling Relation provides us with a methodology for studying one system in terms of another system  (the subject and the "model").

          

           The two systems are related via the encoding and decoding arrows. Encoding is the process of measurement: it is the assignment of a formal label (such as a number) to a natural phenomenon . Decoding is prediction: it is the taking of what we generate via the inferential machinery of the formal system into representations of expected phenomena . Additionally, the arrows for inference and causality represent the entailment structures of their respective systems .

           The modeling relation provides us with a way of ascertaining congruence between the natural system, N, and the formal system, or model, F. What determines successful congruence is that the diagram, as a whole, commutes. That is, such that the numbered arrows meet the condition:  (1) = ( 2) + ( 3) + (4).  This means that our measurements (2), when run through the inferential machinery (3) of our model, will generate predictions (4), which will agree (when verified) with the actual phenomena (1) occurring in N. It bears mentioning that any encoding from N to F is an abstraction and if the modeling relation holds, then F is a model of N.

            If all four conditions of the Modeling relation do not hold, then F is merely a description of N under a specific condition and unable to assist with reflexive anticipation.