 There are two varieties of threshold deontology that are worth distinguishing. On the simple version, there is some fixed threshold of awfulness beyond which morality’s categorical norms no longer have their overriding force. Such a threshold is fixed in the sense that it does not vary with the stringency of the categorical duty being violated. The alternative is what might be called “sliding scale threshold deontology.” On this version, the threshold varies in proportion to the degree of wrong being done—the wrongness of stepping on a snail has a lower threshold (over which the wrong can be justified) than does the wrong of stepping on a baby.