Early on in this book, I observed that one of the recurring questions about error is whether it is basically eradicable or basically inevitable. As a philosophical matter, this question is important, since (as I suggested earlier) the way we answer it says a lot about how we feel about being wrong. As a practical matter, it’s clear that the answer lies somewhere in between: many kinds of error can and should be curtailed, very few can be done away with entirely, and some we shouldn’t even want to get rid of.