[My forthcoming book spends a lot of time contrasting copyright with the common law. I thus thought that I should say at least a little about what I mean by the latter.]
[C]ommon law originates in custom, wins recognition in courts, and develops in commentary. Custom naturally comes first. It long ago gave rise to a set of social practices, such as avoiding bloodshed, honoring borders, and upholding oaths, that permit us to live in peace and prosperity. Referring to those and other customs helps common law courts to resolve our disputes justly. A judge might for instance determine reasonable conduct in a tort case by looking to community standards, award legal rights to someone who has long and openly used property entitled to another, or interpret a contract’s language by light of trade usage. In these and other ways custom inspires—if not mandates—the common law. Commentators, looking back over many court decisions and across many years, help us to follow the common law’s meandering path, explaining and rationalizing its wanderings. The common law thus develops from custom, through courts, and to commentary. [The below figure] illustrates.
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