  There is a sentence in the language of IST, Nelson's internal set theory,
which is not equivalent in IST to a sentence in the ZFC language. Thus the
Reduction algorithm of Nelson, that converts bounded IST formulas with standard
parameters to provably (in IST) equivalent formulas in the ZFC language, cannot
be extended to all formulas of the IST language. Therefore, certain IST
sentences are "meaningless" from the point of view of the standard universe.
