In this paper I provide a unified analysis of a number of pragmatic anomalies that have been discussed in the literature. The paper’s main goal is to account for Sobel sequences of conditionals and sequences of disjunctive sentences, but I will also propose that this analysis can be extended to sequences of sentences with superlatives. The starting point is the observation that, while all these sequences are felicitous in one order, they are infelicitous when the order is reversed. Previous proposals (...) have focussed on particular types of infelicitous sequences Ken Hale: A life in language, MIT Press, Cambridge, 2001; Moss in Noûs 46:516–586, 2012; Lewis in Noûs 52:481–507, 2018; a.o.), or a subset of all the phenomena cited above Linguistic and psycholinguistic approaches on implicatures and presuppositions. Palgrave McMillan, Basingstoke, 2017; a.o.). I propose that sequences of sentences belonging to the same structured set of alternatives T are subject to a Specificity Constraint : sequences are acceptable if both alternatives are dominated by the same number of nodes in the structured set of alternatives T. Violations of SC can be avoided by strengthening the weaker alternative. However, covert strengthening violates an economy condition if the overtly stronger alternative is among those made salient by the preceding utterance in the sequence. I propose that the set of alternatives made salient by an utterance of a sentence s consists of s’s sisters and mother in T. I will show that the strengthening mechanism varies depending on the kind of sequence we have. (shrink)