 The other approach is what we can call a process model. Instead of using various axioms to generate a uniquely rational solution, these theorists rely on some procedure that will generate a determinate, though not always unique result. Process approaches use some mechanism to generate agreement. An example is an auction. There are many types of auctions (e.g., English, Dutch, Vickrey, etc.), each has a way of generating bids on some good and then deciding on a price. Posted price selling, like one often sees in consumer markets, are also a kind of bargain, though an extremely asymmetric one where the the seller has offered a “take or leave it” ask. Double-auctions are more symmetrical and have a clearer link to the initial bargaining model. Although auctions are not typically used to solve pure division problems, there are some examples of auction mechanisms being used to solve public goods problems in interesting ways that guarantee unanimity (Smith 1977). Dworkin also uses a kind of auction mechanism in his work on equality, though he doesn’t develop his approach for more general application (Dworkin 1981, Heath 2004). Despite its promise, however, auction theory and its potential application to social contract theory have largely gone unexploited.