Generics, Frequency Adverbs, and Probability

identifying number 2 would not normally be considered salient; hence the
domain of $1000 bills is homogeneous, and sentence (42)—true.
Frequency Adverbs vs. Generics
We have noted in section 1.8 that all the problematic generics discussed
above would be true if the frequency adverb usually were used instead of
the phonologically null generic quantifier. This provides further evidence for
the claim that frequency adverbs only require homogeneity with respect to
temporal partitions.
Thus, while frequency statements, just like generics,
require regular distribution of events in time, they do not have similar requirements
with respect to other partitions. This, perhaps, is the source of
the rather pervasive intuition that the temporal sense of frequency adverbs is
somehow primary, and the atemporal sense is somehow secondary or derived.
I agree with Lewis (1975) that frequency adverbs may bind both temporal 17
and atemporal variables; but they only require homogeneity with respect to
temporal partitions, regardless of what type of entities they quantify over. 18
17 Or quasi-temporal, e.g. events, situations, occasions, and the like.
18 Alternatively, it might perhaps be proposed that the domain of frequency adverbs
is always temporal, hence can only be considered homogeneous with respect to the time
partition.
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