I had jury duty a few days ago in the Superior Court of the District of Columbia, and as the judge was reading the potential jury members our opening questions (to which we had to mark our answers on an index card), she said the following: "There's nobody whose job is too important for them to not serve on a jury."
The issues involved in (mis-)interpreting sentences like this have been explored and discussed in detail for more than 35 years, starting with Wason & Reich's classic paper "A Verbal Illusion", The Quarterly Journal of Experimental Psychology 31(4):591-97, 1979. Wason and Reich began with the classic clinic-wall warning "No head injury is too trivial to ignore", and went on to propose a theory of such confusions.
That paper, and some of the subsequent work, are discussed at length in "No wug is too dax to be zonged", 11/28/2009. See also "No detail too small", 11/27/2009; and in the unlikely event that you're still interested, "No post too obscure to escape notice", 11/27/2009.
The general idea is that there's
- a scale (here how important someone's job is), and
- a threshold that divides that scale into a lower-valued region and a higher-valued region, and
- a presupposition about how this threshold relates to a binary deontic judgment (here people with less important jobs need to do things like serve on a jury, and people with more important jobs don't), and
- an assertion that the threshold is in fact all the way at one end of the scale or the other (here (the intent is) that the threshold is so high that no one falls into the class "job importance above the threshold".
Things generally work out when the presuppositions and assertions are all commonplace ideas. But when not — as in this case — not.
In addition to the general complexity of interactions amount scalar predicates, modals, and negations, there's an additional problem in this case. Phrases of the form
No one is too X for them to Y
are sometimes interpreted as if they were
No one is so X that they should Y
which doesn't mean the same thing at all.
"Too X to Y" is roughly the same as "so X as to not Y", syntactic details aside. Thus (starting from some real-web "so X as to not Y" examples):
Requirements documents that are so big as to not be understandable are a waste of effort. ==
Requirements documents that are too big to be understandable are a waste of effort.
The policies would be so expensive as to not be worth bothering with. ==
The policies would be too expensive to be worth bothering with.