"The most obvious example of the way law constructs and uses history is found in the doctrine of stare decisis and the practice of justifying present decisions in light of precedent. In the common-law tradition the past is supposed to govern the present. Like cases are to be treated alike. Precedent tells a judge to adhere to the decision in a previous “similar” case. As Shauer notes, an argument “from precedent . . . urges that a decision makers give weight to a particular result regardless of whether that decision maker believes it to be correct and regardless of whether that decision maker believes it valuable in any way to rely on that previous result.” In this understanding, adherence to precedent is a rule, according judges no judgmental discretion. There is, of course, another way of understanding how precedent works that accords judges greater interpretive possibility. Past decisions creates a presumption, but a presumption that can be, and sometimes is, rebutted. Yet both of these conceptions treat the past as discoverable and potentially constraining or authoritative. The judge researching precedent constructs a doctrinal history in the service of elucidating a present problem. These two different ways of thinking about precedent imply two different attitudes toward the past, as commander of the present and barrier to change, or as guide, suggesting paths, but mandating no particular way of being in the present. And beyond these different attitudes toward the past there are the difficulties of determining what counts as an applicable precedent as well as what a precedent stands for in the way of its legal meaning. Neither is self-generating. Analogies proliferate almost without limit. Judges read the relevance of past cases differently, and there are no metarules that govern such determinations of relevance. This is not to say that the search for relevance is a free-for-all. Conventions, habits, institutions, reasons all guide the judgment of what is relevant. Yet judges with different conceptions of their role adopt different standards of relevance as well as entirely different orientations toward the way the past should be used in law."