  Lewis's theory is particularly commendable for its striking  originality and ingenuity and for the simple and straightforward  answers AW1 and AE1 that it provides to our two  questions QW and QE above. Furthermore, because worlds  are (plausibly) defined entirely in nonmodal terms, the truth  conditions provided by Lewis's translation scheme themselves appear  to be free of any implicit modality. Hence, unlike many other popular accounts of possible worlds (notably, the abstractionist accounts  discussed in the following section), Lewis's promises to provide a  genuine analysis of the modal operators. 