 That’s a pretty good characterization of the view that Lewis wanted to demonstrate was inadequate, but we need to generalize a bit to bring Lewis and Perry under the same umbrella. Although possible-worlds propositions were Lewis’s specific concern, the Simple Picture needn’t work with possible worlds propositions in particular—it can operate with any type of proposition in a broader category we’ll call traditional propositions. Traditional propositions determine a possible-worlds truth condition. So they take truth-values relative to worlds. And importantly for our purposes, they don’t take truth-values relative to anything more fine-grained than worlds. So we’ll never get two worldmates standing in the belief relation to the same traditional proposition, one thereby believing truly and the other thereby believing falsely. On the Simple Picture, objects of belief represent ways for the world to be—they impose representational demands on the world, and are answerable to the world for their truth or falsity. Possible worlds propositions are, obviously, like this. So too are standard Russellian structured propositions, constructed out of objects and properties. (The Russellian proposition constructed in the usual way from Aristotle and wisdom is true in all and only the worlds in which Aristotle is wise.)