This paper proposes an alternative view of conditional perfection, i.e. the inference from if p, q to if not p, not q, which is free from the flaws of two major analyses. I show that conditional perfection is an inference which stems from the lexical properties of if. If is semantically related to a yes/no-question, and therefore, induces a set of polarity alternatives, if p, q and if not p, q. The implicature of conditional perfection derives from Horn scale <whether or not, if>, which is constructed from the set of polarity alternatives. Considering the core meaning of if p, q is p's sufficiency for q, i.e. q is true if p is true, the truth of q is an open possibility when p is false. By the way, if if not p, q were also true when if p, q is uttered, then the speaker would be expected to say the more informative whether p or not, q. Since she didn't, the audience infers that it is not the case that whether p or not, q, which consequently leads to the perfection implicature if not p, not q.
I. Introduction II. Two-Competing Analyses III. Proposal IV. Conclusion References