  The preceding arguments for precedent presuppose that decision-makers can correctly ascertain the merits of the cases before them, but law of course operates under non-ideal conditions where decision-makers make mistakes and disagree among themselves about the merits of cases. In practice, the outcome of a case may be uncertain not simply because the correct result is rationally indeterminate, but because the decision-makers are fallible.  Given this, a practice of precedent in law, it can be argued, has a number of advantages due the fact that it may make institutional decisions replicable (see Eisenberg 1988, 10–12, 23–4, whose coinage it is; and Schauer 1987, 597–8).  That a decision is replicable refers to the fact that it is possible for others to make an informed judgement on the likelihood of a particular outcome, in the light of the relevant legal materials, the canons of reasoning used in a system, and an acquaintance with the general culture from which the decision-makers are drawn.  Replicability means that decisions are more predictable than if they were made de novo each time. This, in turn, allows individuals to make plans that are consistent with the law and to avoid falling foul of it, and hence allows them to be guided by the law.