Cross-posted from http://mleseminar.wordpress.com/
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This week we discussed some unpublished material by Antony on ‘might’ counterfactuals. The handout is here, and the paper is here.
We thought a bit about cases in which ‘could’ and ‘might’ come apart. In the paper, Antony discussed sentences like
33b) If we’d left the gate open, the dog could have got out; yet if
we’d left the gate open, it isn’t the case that the dog might have got
out.
The felicity of such sentences seems to show that at least some
‘might’ counterfactuals shouldn’t be analysed in terms of ‘could’, but
instead should be given an epistemic reading. Antony isn’t averse to
this idea – in fact, his final view is that ‘might’ is ambiguous in
counterfactual contexts between the epistemic reading and the ability
reading. However, this does invite the further question of what
determines the appropriate reading for some given ‘might’
counterfactual.
Fron 33b we naturally conclude though the dog has the ability to get
out, it is so disposed as to not exercise this ability. The only way
to interpret someone who expresses the conjunction as not contradicting
themselves is to give the ‘might’ and the ‘could’ different readings,
and the ‘could’ tends to snaffle the ability reading, leaving the
epistemic reading for the ‘might’. 33a, on the other hand, is
intuitively clashing:
33a) If we’d left the gate open, the dog might have got out; yet if we’d left the gate open, the dog couldn’t have got out.
An explanation for this would be is that the ‘might’ in the first
conjunct naturally takes an ability reading, which the second conjunct
then contradicts. If this is right, then it looks like ‘the dog
couldn’t have got out’ always takes an ability reading, while ‘the dog
might have got out’ can take both the ability and epistemic readings.
This suggests the following difference between ‘might’ and ‘could’
in counterfactual contexts. When used as a predicate, as in the
examples above, can/could always takes the ability reading.
It only takes the epistemic reading when used as a sentence modifer, as
in ‘it could be that the dog escaped’. May/might, on the other hand,
can take either the epistemic reading or the ability reading
when used as as a predicate. Like can/could, may/might always takes an
epistemic reading when used as a sentence modifier.