 What if \(A\) does contradict your existing beliefs? Then \(K + A\) wouldn’t do, since it would be inconsistent. We’d have to remove some of your existing beliefs to make room for \(A\). Luckily, for our purposes here we don’t have to worry about how this works. We’ll only consider cases where \(A\) is consistent with \(K\), in which case \(K + A\) will do.