The argument for using closeness to conventional morality to break ties between otherwise equally promising codes begins with the observation that social change regularly has unexpected consequences. And these unexpected consequences usually seem to be negative. Furthermore, the greater the difference between a new code and the one already conventionally accepted, the greater the scope for unexpected consequences. So, as between two codes we judge to have equally high expected value, we should choose the one closest to the one we already know. (For discussion of the situation where two codes have equally high expected value and seem equally close to conventional morality, see Hooker 2000: 115. For a more nuanced view, see Hooker 2008: 83–4.)