Why isn't saying "I don't know" a reasonable approach to the issue when ones knowledge is vague enough to be useless for knowledge (and can only be made useful if the case was a bizarre thought experiment), Just because one couldtheoretically bet on something doesn't mean one is in a position to bet. (For example to say that I don't know how to cure a disease so I will go to the doctor, or I don't know what that person's name is (even though I know it isn't "Xpchtl Vaaaaaarax") so I should ask someone, Or I don't know how life began. Or I don't know how many apples are on the tree outside (even though I know it isn't 100 million))