Quotes about Ad hoc-ness

Among this pool are these: (a) explanatory power, (b) explanatory scope, (c) plausibility, (d) degree of ad hoc-ness and (e) conformity with other beliefs. The more explanatory power and scope and the more plausibility and conformity with other beliefs an explanation has, the better it is. The less ad hoc (adjusted, contrived, artificial) the explanation, the better as well. The trick is to subject all explanation options to these criteria.