4. Vagueness and context

4. Vagueness and Context

• Vague expressions can often not be interpreted without context

• We know (roughly) how to apply `tall` to a person. Roughly: Tall(x) Height(x) >> 170cm

• If we used the same standards for buildings as for people, than no building would ever be tall!

• Context-dependence allows us to associate one word with very different standards. Very efficient! (Cf. Barwise & Perry, “Situations and Attitudes”)

Variant of old example

[[animal]] = {a,...,k}

[[black]] = {a,b,c,d,e}[[cat]] = {a,b,f,g,h,i,j}

[[elephant]] = {c,d,e,k}

[[black cat]] = {a,b,c,d,e} {a,b,f,g,h,i,j} = {a,b}

[[small elephant]] = ?

[[small]] = ? Any answer implies that

x is a small elephant x is a small animal

Other types of vagueness are also context dependent

• [[many]] = how many?• [[(increase) rapidly]] = how rapidly?• temporal succession. Compare the time lags

between the events reported:

1. ``John entered the room. [..] He looked around.less than a second

2. ``Caesar came, [..] he saw, [..] he conquered``weeks or months

3. ``The ice retreated. [..] Plants started growing. [..] New species appeared.``many years