## Notre Dame Journal of Formal Logic

### A Remark on Henkin Sentences and Their Contraries

John P. Burgess

#### Abstract

That the result of flipping quantifiers and negating what comes after, applied to branching-quantifier sentences, is not equivalent to the negation of the original has been known for as long as such sentences have been studied. It is here pointed out that this syntactic operation fails in the strongest possible sense to correspond to any operation on classes of models.

#### Article information

Source
Notre Dame J. Formal Logic Volume 44, Number 3 (2003), 185-188.

Dates
First available: 28 July 2004

http://projecteuclid.org/euclid.ndjfl/1091030856

Digital Object Identifier
doi:10.1305/ndjfl/1091030856

Mathematical Reviews number (MathSciNet)
MR2130790

Zentralblatt MATH identifier
02187148

#### Citation

Burgess, John P. A Remark on Henkin Sentences and Their Contraries. Notre Dame Journal of Formal Logic 44 (2003), no. 3, 185--188. doi:10.1305/ndjfl/1091030856. http://projecteuclid.org/euclid.ndjfl/1091030856.

#### References

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• [4] Walkoe, W. J., Jr., "Finite partially-ordered quantification", The Journal of Symbolic Logic, vol. 35 (1970), pp. 535--55.