premise: But if you are sure that you have enjoyed to the full the reaction of joy after despair with which I have kindly provided you free of charge, let us get down to our mail, as the saying goes." Tuppence snatched the two precious envelopes from him unceremoniously, and scrutinized them carefully.
hypothesis: Tuppence had no intention of returning the envelopes, but she wanted to make sure they were the right ones.