 First, an adequate theory should be minimal, in the sense that it posits just enough perfectly natural properties and relations for their distribution among the fundamental particulars to fully and determinately fix the nature of all of reality: “The guiding idea, roughly, is that the world’s universals should comprise a minimal basis for characterizing the world completely. Universals that do not contribute at all to this end are unwelcome, and so are universals that contribute only redundantly.” (1999, p. 12) It is clear from the surrounding text that Lewis takes this constraint to govern the various alternatives to a universals account of  naturalness.[3]