Cornered Cat has a good post up on why there are four safety rules in The Four Rules. As Uncle said, it takes violating two or more of The Four Rules to cause tragedy.
Not one of the safety rules, by itself, will prevent an unintentional shot. Not one. They are intended to overlap and provide redundant layers of safety. Even all four of the rules together do not entirely prevent unintentional shots. Following all four safety rules simply reduces the consequences when mistakes are made, ensuring that only things we don’t mind shooting get shot.
Read the whole thing, it’s well worth your time.
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