Which criterion is NOT used when judging explanatory power?

• A. Simplicity criterion
• B. Generality criterion
• C. Empirical criterion
• D. Specificity criterion

Answer: (A)

The simplicity criterion is not typically used when judging the explanatory power of a theory or model. In the context of evaluating explanatory power, emphasis is placed on how well a theory can account for a variety of phenomena and its relevance across different contexts, which aligns with the generality criterion. The empirical criterion focuses on the degree to which theories can be supported by observable and measurable evidence, making it crucial in establishing a theory's validity. The specificity criterion relates to how precisely a theory can make predictions or explain specific cases.

While simplicity is often valued in scientific theories for its role in aiding understanding and communication, it is not itself a measure of a theory's explanatory power. The latter is more concerned with how effectively and broadly a theory can operate within its domain, rather than how simple or complex that theory might be. Thus, the correct choice reflects the lack of relevance of the simplicity criterion in evaluating explanatory power.