Modularity is a familiar feature of law, under whatever authority it is developed. Depending on the history and culture out of which law arises, it is conceived as being divided into different, non-overlapping subject areas. These subject areas are then codified, reflecting the cultural expectations out of which the law arises. The division into different subject areas is useful for efficient administration of justice, among other things. Legal specialties can evolve, and by the economic force of comparative advantage operating through division of labor, more efficiently resolve legal questions. Subject divisions are also used for political purposes, to enable favored entities to capture particular areas of law while leaving other areas open to greater competition. Although resistant to political capture, voluntary law shares a potential for modularity with other forms of law, and can also be divided into subject areas.

Were this all that could be said about modularity, it might be of relatively scant interest. Within the field of voluntary law, however, modularity looms large as a tool of importance for resolving legal conflicts. Voluntary law is capable of exploiting a much more finely-grained and sophisticated modularity than we are used to seeing in traditional legal systems, for new purposes. These purposes include efficient conflict resolution among arbitrarily large sets of conflicting laws. To illustrate, suppose a million different strains of voluntary law are in use by a billion different persons speaking a hundred different languages. That’s a lot of variety. In such an environment, a jurist might practice law for a lifetime without ever encountering a dispute involving exactly the same sets of laws.

How could a jurist manage to be expert in such a great variety of laws? Wouldn’t such a system be prohibitively inefficient and expensive? Not necessarily. It all depends on the information tools available. If the million different voluntary laws can be translated into a uniform logical language to create expressions that can be mapped onto a hierarchy of finely-grained subject areas, the process might go something like this: The claimant identifies the law on which the claim is based. The defendant identifies affirmative defenses. The jurist, assisted by automatic translation algorithms, translates the submitted laws into the uniform logical language. Once the submitted laws are translated, the jurist assisted by automatic mapping algorithms maps the laws into the subject area hierarchy. Broader, more general laws may map into more than one subject area category, and more particular laws into fewer areas, or into only one subject area. Using the subject area hierarchy, the jurist identifies the corresponding laws adopted by each of the adverse parties, and any earlier laws adopted by the parties in the same subject areas. If there are no corresponding laws found, the jurist may determine that one of the parties is an outlaw in the subject area and inform the parties that the case cannot proceed unless the parties agree on the law to be applied. If corresponding laws are found, the jurist applies a conflict of law analysis, for example TROTWET, to identify the applicable laws of the case.

What might cause a million different voluntary laws in a hundred different languages to be capable of translation into a uniform logical language? No special cause is needed; the capability is inherent in the semantic character of language itself. Some expressions may be more easily translated than others. Economic pressure would cause most laws to be expressed in a readily translatable form, because choosing such forms saves resources (e.g., money) without putting any constraints on what may be expressed. Providers of services for conveniently selecting and publishing adoption of voluntary laws would, under market pressure, offer services enabling virtually any law to be expressed in a form that can readily be translated and mapped onto a standard hierarchy of subject areas. If they did not, other providers would eventually replace them.

Some laws may include semantic content that is not found in other laws, which therefore cause the law to be mapped to a unique subject area. For example, the laws of Amazonian jungle tribes might include concepts with no equivalent meaning outside of the Amazon, such as laws relating to things or events that are peculiar to that river basin or culture. Laws that exist in a unique subject area cause every person not adopting the law to be an outlaw in the subject area. To avoid inadvertently falling into an outlaw status, a prudent traveler might prepare for a journey by researching unique subject areas that are predominate along the planned trail, and adopting suitable laws in those subject areas beforehand. In the alternative, a reasonable traveler, if unexpectedly sued under a unique law in a place where the unique law is customary, might agree to resolution of the dispute under the customary law instead of taking chances on extra-legal resolution in a strange location.
If a law in a unique subject area is not customary, a defendant sued under the odd law would have little incentive to agree to resolution under it, and might happily remain an outlaw in the odd subject area.

To use a rather silly example, suppose “Jester” adopts an odd law that any person found with more than a tenth gram of lint in their navel must pay a fine to the discoverer of the lint. He goes about the beach with a portable scale, discovering navel lint and serving notices of complaint to the bathers. No reasonable bather would bother responding to such a complaint, presuming Jester is alone or nearly alone in adopting what is truly an odd law. The reputation of an outlaw stings only when the subject area is customarily a subject of law. Depending on Jester’s law and actions, some might respond by suing him for something akin to malicious prosecution, invasion of privacy, or assault. Navel-gazers like Jester gain nothing but notoriety and increased risk of liability by complaining over legal oddities. However, to be socially fashionable, funny, or for other non-economic reasons, some might choose to respond to news of Jester’s odd exploits by proactively adopting their own laws on the subject of navel lint, for example, defensive laws expressing that no fines or other liability shall be assessed for navel lint, regardless of amount, or retributive laws assessing fines for examining the navels of others without express written permission. Given the ease with which voluntary laws can be adopted, and the character of wit at play, a degree of harmless frivolity should be expected to naturally arise. More significantly, as social consciousness evolves laws in subject areas initially thought to be odd may grow in popularity to become customary, and customary subject areas may grow to become odd.

It might be wondered whether a logical dilemma arises when a broadly-written law spanning several subject areas is asserted against a defendant (or conversely, a broadly-written affirmative defense is raised against a complainant) who holds more particular laws categorized in separate subcategories. Which of these more particular laws should the jurist select as the opposing law? There is actually no dilemma, assuming the jurist analyzes the case under TROTWET. If the complainant’s law is broader, the complaint must be decided under the particular subject area of defendant’s law that is most applicable to the facts of the case. Therefore the complainant’s broader law will apply only if it results in less liability than defendant’s law, under the facts of the case. Conversely, if the defendant’s law is broader, one of complainant’s laws that is applicable under the facts of the case will apply only if resulting in less liability than defendant’s law. If laws held by the same party in different subject areas are equally applicable to the case and result in exactly the same liability, it makes no difference which is applied. The same analysis applies for affirmative defenses, the only differences being that the most applicable one of complainant’s more particular laws will govern the choice of law when the complainant holds more particular laws, and as between complainant’s and defendant’s laws, the affirmative defense that results in the greatest liability for the defendant is the chosen law.

As illustrated by the foregoing, modularity in voluntary law provides the important function of enabling efficient conflict resolution among adopted laws of arbitrarily large diversity, guides development of law by motivating the development of standard subject area hierarchies and readily-translatable forms of expressing laws, and facilitates social experimentation both in defining new legal subject areas and phasing out archaic subject areas. It cannot be imagined beforehand what forms these evolving new aspects of voluntary law might take, in any but the vaguest form. It is hoped that these words will help others glimpse the potential for amazing new forms and expressions of law that will only faintly resemble the oppressive laws of the present day, and that will enable the light of justice to shine more brightly than possible ever before. Modularity has other uses in harmonizing with non-voluntary legal systems, which will be discussed later.