In
J.L. Austin's speech act theory, an
utterance is said to be unhappy when:
- The utterance is performative, which is to say that it does something as opposed to simply sating something. The most common example of a performative utterance is the phrase "I do" when spoken in the context of a marriage ceremony; but
- The context for the speech act is wrong. This can be due to purely circumstantial events (ie, saying "I do" outside the marriage ceremony will not result in marriage) or it can be due to the mindset of the speaker. For example, an insane person who says "I do" during an otherwise appropriate marriage ceremony may not have the presence of mind to enter in to such an arrangement and will not be considered married.
To use another of Austin's examples, one can name a ship by speaking some words and smashing it with a bottle, but only if one has the
authority to do so. This is what keeps me from naming ships
recreationally, since I think it would be lots of fun to wander down to the
harbor, fold up my newspaper and say, with a proper grandiose
flourish, "That's a lovely ship. I think everyone shall call her the
HMS Steve." That would be an unhappy utterance, and I do so hate to make my utterances miserable.
Sources:
Austin, J.L.  How to Do Things With Words, 2nd ed. 1975: Harvard University Press.