I rather like the 3rd answer on his blog (Doug D’s). A slight elaboration on that—one virtue of a scientific theory is its generality, and prediction is a better way of determining generality than explanation—demanding predictive power from a theory excludes ad hoc theories of the sort Doug D mentioned, that do nothing more than re-state the data. This reasoning, note, does not require any math. :-)
I rather like the 3rd answer on his blog (Doug D’s). A slight elaboration on that—one virtue of a scientific theory is its generality, and prediction is a better way of determining generality than explanation—demanding predictive power from a theory excludes ad hoc theories of the sort Doug D mentioned, that do nothing more than re-state the data. This reasoning, note, does not require any math. :-)