… we generally choose to use vague terms like “tall” or “red” even though the English language allows us to say “6 foot 5.2 inches” or to define a color in terms of CMYK…
Il perché di questa scelta è avvolto in un mistero mai dipanato a dovere.
A nulla vale ipotizzare l’ utilità della parola vaga nell’ opera di depistaggio di chi ascolta: il linguaggio vago viene usato anche in contesti dove gli interessi degli interlocutori sono perfettamente allineati.
Ma forse, per capire meglio il “mistero” di cui parlo, è utile un esempio:
… for example, the speaker may need the listener to pick up a friend at the airport, and want to describe the friend’s height. Both players have the same utility function, so there is no conflict of interest…
E il problema dove sta (dirà ancora qualcuno)?
In this story, a vague statement is just a strange strategy… for example, imagine the message space is “tall” and “short”. A vague language has the speaker say “tall” when the friend is above six feet, say “short” if below five foot eight, and play a mixed strategy if the height is inbetween. A precise strategy picks some cutoff, says “tall” is above the cutoff, and “short” otherwise.
A one-line proof shows that the precise language always gives higher utility to both players than the vague language.
L’ esempio è utile in poiché illustra quanto siano poco calzanti quelle spiegazione che troviamo naturali di primo acchito:
So what explains vagueness…?
It’s not a matter of using a more limited vocabulary: in the example above, “tall” and “short” are the only words in both the vague or the precise cases.
It’s also not a matter of context-flexibility. In both the vague and precise cases, we still need some sense of what tall means when referring to coffee and what tall means when referring to NBA players.
It’s not even a matter of the impossibility of precision: the phrase “tall” can precisely refer to an interval, or precisely refer to a distribution…
Primo tentativo di soluzione:
… may be people use vague speech because they have a vague understanding of the world; that is, people do not actually form, say, a subjective probability distribution over the height of who they are talking about…
Direi poco soddisfacente: perché mai un’ incertezza non potrebbe tradursi in una probabilità soggettiva?
Veniamo a qualcosa di meglio:
… vagueness can actually help search…
Un modo per minimizzare il rischio di malintesi. Esempio:
Imagine asking someone to grab a blue book for you, and imagine that we have slight perceptual differences in how we see color.
If blue is precisely defined, then your friend will first look through your blue books (as he perceives them), and if he does not see the book you want, will have to search through the rest of your collection at random.
If blue is vaguely defined, your friend will first look through all the books he considers “bluish”, and only after doing that will search the rest of your collection. When there is a sufficient lack of overlap in our conceptions of blue, the vague search will be quicker….
Bart Lipman – Why is language vague?