Steven Horwitz reminds us at The Freeman:
Hayek emphasized that one of the great advantages of the liberal market order is that by requiring agreement on only a small number of things, the scope for peaceful coexistence and collaboration is widened among people who disagree on many other things. One need only recognize that people with different consumer preferences manage not only to coexist with one another but also engage in mutually beneficial trade with producers who meet those various needs. Even more generally, liberal societies enable people with different values and ideas about life to find peaceful ways of interacting to achieve their respective goals.
Hayek understood that the only way a society can respect diversity is if people agree on basic rules, especially what he called “ends-independent” rules of justice. These rules must permit all individuals to pursue their own ends peacefully rather than being aimed at specific social ends. That is, the rules cannot have a concrete purpose; rather, they must be general enough to allow the achievement of a variety of purposes.
Like Money and Language
In this way the rules of justice are analogous to money or language, both of which can be seen as “ends-independent” means for achieving a variety of ends. Money and language have no purpose of their own. They are simply means by which people pursue their own particular purposes and plans. Moreover, they permit peaceful interaction among people who disagree about ends.
So it is with the legal order of a liberal society. Instead of our having to agree on the ends, with the State controlling the means, markets allow us to agree on the means while respecting a diversity of ends.
Note that classical liberalism still requires a common commitment, not to a set of ends or values, but to a set of means that comprise legitimate behavior under the rule of law. The agreement on private property, contract, and exchange as legitimate means to one’s ends, as well as the agreement that force and fraud are illegitimate means, are what unite the members of a liberal order.
It is this that makes peaceful disagreement about ends possible. The liberal order is the only way to achieve a society in which diverse preferences, values, and ends are truly respected. Indeed, classical liberalism’s emphasis on agreement over means nourishes the diversity of ends. However, once we take the social-justice approach and begin to demand agreement on ends, we eradicate the possibility of peacefully coexisting with those whose ends differ. In other words, social justice can kill real diversity.