Your friend Bill believes that he can heal anyone from illness by chanting their names while holding a special crystal. He agrees on a test of this claim. You find 20 people who are sick, and split them randomly into two groups. He chants the names of the people in one group while holding his crystal, and then you check to see how well the two groups feel afterwards. In the end, there is no difference between the two groups. Now Bill wants to engage in a little ad hoc modification. Identify a more specific claim about his healing powers that he could adopt instead, with these two features: (i) your test provides no evidence against this new claim; (ii) it entails that he can at least heal some people with his method. What, if anything, would be wrong with Bill being just as confident in this new claim as he was in his original claim?