Use-mention distinction

The use-mention distinction is the distinction between using a word (or phrase, etc.) and mentioning it. In written language, mentioned words or phrases often appear between quotation marks or in italics; some authorities insist that mentioned words or phrases always be made visually distinct in this manner. Used words or phrases, being more common than mentioned ones, do not have any typographic distinction.

For example,

Cheese is derived from milk.

is a statement about the substance cheese, while

Cheese is derived from a word in Old English

is a statement about the word cheese.

Putting a statement in quotation marks and attributing it to its originator is a useful way of turning a disputed statement about a subject into an undisputed statement about another statement.

Making a statement mention itself is an interesting way of producing logical paradoxes. There are many examples of this phenomenon in the works of Douglas Hofstadter.

Violation of the use-mention distinction can produce sentences that sound and appear similar to the original, but have an entirely different meaning. For example,

"The use-mention distinction" is not "strictly enforced here."

is literally true because the two phrases in it are not the same.

Use-mention and Suppositio

The general property of terms changing their reference depending on the context was called suppositio (substitution) by classical logicists. It describes how one has to substitute a term in a sentece by its meaning ---i.e. what referent the term has. In general, a term can be used in several ways. For nouns, they are:

• Properly with a real referent, as in "that is my cow" (assuming it exists).
• Properly with a generic referent, as in "Any cow gives milk".
• Properly but with a non-real referent: "Ulises' cow was big".
• Unproperly by way of metaphor: "You are a cow" (metaphor).
• As a pure term: "cow has only three letters".

The last use is what gives rise to the use-mention distinction.

Journalism

In journalism, the use-mention distinction is often used when reporting on scandals. Rather than saying "Jeffrey Archer is a crook", an article might say "There have been allegations that Jeffrey Archer is a crook". Or, more concisely, "Jeffrey Archer is allegedly a crook". Journalists claim to be reporting allegations, rather than making allegations.