Sunday 13 July 2008

Dudman's Fourth Category

V. H. Dudman has identified three major categories of messages expressible in English if-sentences: (1) hypothetical, (2) habitual, and (3) conditional.  These categories may be exemplified in turn by the natural interpretations of the following sentences:

(i)  If Socrates was a man, he was mortal.
(ii)  If Baby cries, we beat him.
(iii)  If Oswald doesn't shoot Kennedy, someone else will.

In §4.7 of ‘Antecedents and Consequents’ (1986), Dudman discerns an egregious fourth category, (4), which he exemplifies with:

(iv)  If Tom was fat, his sister was immense.

Grammatically, the difference between (1) and (4) is supposed to be that (4) forces the if-string to prefix the independent sentence, whereas (1) allows freer amalgamation.  Semantically, in category (4) the ‘common trait seems to be apposition: while the independent message is affirmed outright, the 'dependent' message is there for the sake of analogy, pointing up a similarity or contrast, perhaps suggesting a comparison.’  In (1), by contrast, the independent message is normally affirmed only on the given hypothesis.

Dudman's sample sentence (iv) is unhappy, as it is easily interpreted as encoding a hypothetical.  (Compare: ‘If Kate Moss is fat, I'm morbidly obese.’)  To facilitate discussion of category (4), we need to use clearer examples.  I am compiling a list of them here.