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1. • CommentRowNumber1.
   • CommentAuthorUrs
   • CommentTimeApr 8th 2011
   • PermaLink
   Author: Urs
   Format: MarkdownItexcreated stub for [[Barr's theorem]] (If a statement in [[geometric logic]] is deducible from a [[geometric theory]] using classical [[logic]] and the [[axiom of choice]], then it is also deducible from it in [[constructive mathematics]].)

   created stub for Barr’s theorem (If a statement in geometric logic is deducible from a geometric theory using classical logic and the axiom of choice, then it is also deducible from it in constructive mathematics.)

2. • CommentRowNumber2.
   • CommentAuthorzskoda
   • CommentTimeApr 8th 2011
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   Author: zskoda
   Format: TextJust a reminder. There is also another theorem sometimes referred as Barr's theorem, or more precisely, the Barr embedding theorem.

   Just a reminder. There is also another theorem sometimes referred as Barr's theorem, or more precisely, the Barr embedding theorem.
3. • CommentRowNumber3.
   • CommentAuthorThomas Holder
   • CommentTimeMay 9th 2020
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   Author: Thomas Holder
   Format: MarkdownItexExpanded a bit on the eliminability of non-constructive proofs with respect to geometric theories and sequents. <a href="https://ncatlab.org/nlab/revision/diff/Barr%27s+theorem/9">diff</a>, <a href="https://ncatlab.org/nlab/revision/Barr%27s+theorem/9">v9</a>, <a href="https://ncatlab.org/nlab/show/Barr%27s+theorem">current</a>

   Expanded a bit on the eliminability of non-constructive proofs with respect to geometric theories and sequents.

   diff, v9, current