Symmetry by three archetypes of scientific theories

Table: Symmetry by three archetypes of scientific theories

Introduction: Although the nature of scientific theories can be either explanatory, predictional, exemplary or something in between these three archetypes (see below and click the names), the structure of such theories is always symmetrical in the sense that scientific theories are made up by an explanans produced by induction and an explanandum produced by deduction of explanans. See the covering law model.

Note: All bold text in table below can be clicked to obtain more information

Quasi-sciences: E.g., economics

Exemplary sciences:

E.g., physics

Explanatory theory

'the Machlup [1955] approach'

Predictional theory

'the Friedman [1953] approach'

Exemplary theory

Unknown explanans

Explanans has to be found by empirical investigation of facts. This is empirical induction the strength of explanatory theory.

Assumed known explanans

Explanans is constructed by use of a few realistic assumptions and many unrealistic but simplifying assumptions. This is hypothetical induction the weakness of predictional theory.

Unknown explanans

Explanans has to be found by empirical investigation of facts. This is empirical induction one of the strengths of exemplary theory.

Assumed known explanandum

Explanandum is made by use of wildly unrealistic but simplifying intuition. This is intuitive deduction the weakness of explanatory theory.

Unknown explanandum

Explanandum has to be found by algebraic manipulations of mathematical models. This is logical deduction the strength of predictional theory.

Unknown explanandum

Explanandum has to be found by algebraic manipulations of mathematical models. This is logical deduction one of the strengths of exemplary theory.