 While minimizing regressive mind changes is an even more important epistemic goal than avoiding mind changes in general, it leads to weaker strictures on inductive learning. At the same time any strictures that do follow from it carry even more normative force. The table above illustrates the differences between the two principles in the New Riddle of Induction and the Raven problem. In the New Riddle of Induction, if only green emeralds are ever observed, a projection rule may keep projecting any number of gruesome predicates without producing a regressive mind change: it simply abandons one false gruesome predicate for another false gruesome predicate. Therefore even unnatural projection rules incur 0 regressive mind changes, provided they never abandon “the all green hypothesis” once adopted.