 namely, their subject matter. The subject matter of a sentence in context can be seen as a topic, an issue, or a question the sentence may be taken, in that context, as answering to. When the issue is the number of stars, the relevant question may be: “How many stars are there?”. As in inquisitive semantics (Ciardelli, Groenendijk, &amp; Roelofsen 2013), one can associate the question with the set of its answers: There are no stars; There is one star; There are two stars; etc. Answers are propositions in the SPWS sense: sets of possible worlds. We now call these thin propositions for the full propositional contents of sentences will turn out to be richer than that. The question, thus, splits the totality of worlds into sets (the relevant thin propositions). Two worlds \(w_1\) and \(w_2\) end up in the same set just in case they agree on the answer—in our example: when the number of stars is the same at \(w_1\) and \(w_2\). When, as in the example, the question has just one correct answer, the thin propositions at issue form a partition of the set of worlds \(W\): a splitting into subsets such that their union is all of \(W\), and such that each \(w\) in \(W\) is in exactly one subset or cell. One cell has all the 0-star worlds, one all the 1-star worlds, one all the 2-star worlds, and so on.