 In some cases we can make something the case by saying that it is. Alas, I cannot lose ten pounds by saying that I am doing so, nor can I persuade you of a claim by saying that I am doing so. On the other hand I can promise to meet you tomorrow by uttering the words, “I promise to meet you tomorrow,” and if I have the authority to do so, I can even appoint you to an office by saying, “I hereby appoint you.” (I can also appoint you without making the force of my act explicit: I might just say, “You are now Treasurer of the Corporation.”) Only an appropriate authority, speaking at the appropriate time and place, can: christen a ship, pronounce a couple married, appoint someone to an administrative post, declare the proceedings open, or rescind an offer. Austin, in How To Do Things With Words, details the conditions that must be met for a given speech act to be performed felicitously.