It is frequently said that a good theory is one which can in principle be refuted by an empirical, data-oriented study. Describe why a theory which cannot be evaluated empirically is not a good theory.
In evaluating theory there are two steps: firstly, you have to examine the reasonability of the theory's assumptions; secondly, you have to test the theory's predictions by comparing them with facts. If a theory cannot be tested, it cannot be accepted or rejected. Hence, it contributes little to our understanding of reality.