The argument basically proceeds as follows:
In both Greek and Roman societies, rights were thought of as by-products of duties, which in turn were linked with status and social role. For example, heads of households had duties owed to that status, and consequently enjoyed rights not available to other members of the household. The same phenomenon was tied to military status, membership in the clergy, etc. As members of the human race, people in ancient Greece and Rome had no rights. Apparently the Confucian concept was the same. For example, Roman commercial law (known for some strange reason as the Law of Foreigners) was available only to those whose duties required it.

Fast forward to medieval Europe, where commercial need for contracts was growing but commercial contractual law is missing. The established law courts were shaped by feudal law, the rule of rank, or hierarchical law. Commercial people, on their own for hundreds of years, developed binding courts of arbitration outside official courts, which accreted bodies of precedent and eventually became known as the Custom of Merchants.

This contractual law, which was eventually incorporated into the body of established law (in the case of England, by act of Parliament), contained a radical notion. It applied to all individuals alike, for no other reason than that they were individuals, making binding contracts, no matter who they were or what their social status was.

According to Jacobs, neither rulers nor philosophers invented individual rights. They were a product of the market. This jibes with linguist Charles Fillmore’s claim that all categories are rooted in motivating experiences and social knowledge.

Therefore, excessive government interference in the market not only threatens bare economic well-being, but may also erode the social practices which nourish and sustain the notion of ‘individual rights’, and perhaps even the belief in the possibility of a self-governing people (ie, democracy).

[As an aside, Jacobs’s book posits the existence of two separate norm-sets which govern ‘guardian’ work and ‘commercial’ work. Her analysis (which pools numerous snippets of fascinating history) shows that a healthy society requires not only the segregation of these functions - in accord with Milton Friedman - but their successful symbiosis. She deftly demonstrates how most failed social systems, from the Soviet Union to the Khmer Rouge, from the Mafia to many defense contractors, represent blendings of these normative systems.]