J. L. Austin — English Philosopher born on March 28, 1911, died on February 08, 1960

John Langshaw "J. L." Austin was a British philosopher of language and leading proponent of ordinary language philosophy, perhaps best-known for developing the theory of speech acts... (wikipedia)

Going back into the history of a word, very often into Latin, we come back pretty commonly to pictures or models of how things happen or are done.
Sentences are not as such either true or false.
In the one defence, briefly, we accept responsibility but deny that it was bad: in the other, we admit that it was bad but don't accept full, or even any, responsibility.
Usually it is uses of words, not words in themselves, that are properly called vague.
Infelicity is an ill to which all acts are heir which have the general character of ritual or ceremonial, all conventional acts.