Law and equity are not so opposed after all, if equity acts as a safety valve aimed at preventing opportunism. Instead, an information-cost theory of property points to a limited role for equity to protect the formal rules of the law against opportunistic exploitation. Thus, within the law, micro equity need not undermine the rule of law, but rather reinforces it. And at the level of the legal system itself, the problem of opportunistic and disingenuous satisfaction of thin notions of the rule of law point to a similar need for macro equity – a limited invocation of standards outside the system of formal law. At both levels, the information-cost theory converges with a morality of the law that requires both formalism and equitable intervention against opportunistic evasion of formal systems.