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In article <1993Jan12.201545.27599@CSD-NewsHost.Stanford.EDU> pratt@Sunburn.
Stanford.EDU (Vaughan R. Pratt) writes:

   >Australian and American courts interrogate witnesses in a language that
   >presumes intuitionistic logic, in that they draw a distinction between
   >straight answers and hedged and insist on the former.

  The distinction between hedging and straight answers has nothing in
particular to do with intuitionistic logic, and your statement that it
"presumes intuitionistic logic" is quite arbitrary.  Furthermore,
natural language is not a formal system, and I doubt that it is
possible to find anything in the use of natural language corresponding
e.g. to the intuitionistic validity of the double negation of Peirce's
axiom.  This applies equally, of course, to classical propositional
logic. Formal logic doesn't tell us a great deal about what reasoning,
interrogation, justification, etc in natural language is like.

  More interesting is the other point you raised, concerning the
possibility of interpreting classical in intuitionistic theories via
e.g. a Godel translation, where you emphasized that the effect of this
is to introduce distinctions where there are none in classical logic.
But clearly this in itself tells us nothing about the usefulness or
interest of the intuitionistic versions of the theories. We can go on
to introduce a large number of logical distinctions, still with
Godel-type translations of classical theorems.  Such distinctions have
no intrinsic value. Looking at the distinctions introduced by
intuitionistic logic, they are in part natural in the sense that they
have a connection with or correspond to distinctions that we make in
mathematics and that we have found useful, such as the distinction
between direct and indirect proofs of existential statements. But
intuitionistic logic involves very much more than such natural
distinctions. For example, the logical distinction between ~~ExP(x)
and ExP(x), with P a decidable number-theoretic predicate, corresponds
to nothing in ordinary mathematical experience. For another example,
the splitting up of the concept of an infinite set of natural numbers
into "infinite", "not not infinite", "not bounded" introduces
considerable complications, and we don't even know whether it is possible to
teach and learn mathematics without "conflating" these concepts. We need
to think about such matters as well in considering distinctions.