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1. • CommentRowNumber1.
   • CommentAuthoratmacen
   • CommentTimeJan 21st 2019
   • PermaLink
   Author: atmacen
   Format: MarkdownItexThe example of $Q$ as a Bishop set on the preset $Z \times Z$ is wrong. You need to rule out zero denominators. The definition currently on the page is not a Bishop set at all, because $0/0$ makes the relation intransitive. I'm not sure how it should be changed to illustrate the point that the same preset can get distinct sets. Maybe a different example entirely? <a href="https://ncatlab.org/nlab/revision/diff/preset/17">diff</a>, <a href="https://ncatlab.org/nlab/revision/preset/17">v17</a>, <a href="https://ncatlab.org/nlab/show/preset">current</a>

   The example of $Q$ as a Bishop set on the preset $Z \times Z$ is wrong. You need to rule out zero denominators. The definition currently on the page is not a Bishop set at all, because $0/0$ makes the relation intransitive.

   I’m not sure how it should be changed to illustrate the point that the same preset can get distinct sets. Maybe a different example entirely?

   diff, v17, current

2. • CommentRowNumber2.
   • CommentAuthoratmacen
   • CommentTimeJan 21st 2019
   • PermaLink
   Author: atmacen
   Format: MarkdownItexOh wait. False alarm. That text is using $Z$ for *positive* integers only.

   Oh wait. False alarm. That text is using $Z$ for positive integers only.

3. • CommentRowNumber3.
   • CommentAuthorAli Caglayan
   • CommentTimeJan 21st 2019
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   Author: Ali Caglayan
   Format: MarkdownItexThat's a weird convention, probably best to change it no?

   That’s a weird convention, probably best to change it no?

4. • CommentRowNumber4.
   • CommentAuthoratmacen
   • CommentTimeJan 21st 2019
   • PermaLink
   Author: atmacen
   Format: MarkdownItexChanged the notation in the example that confused me: added "+" superscripts to the (pre)set symbols. <a href="https://ncatlab.org/nlab/revision/diff/preset/18">diff</a>, <a href="https://ncatlab.org/nlab/revision/preset/18">v18</a>, <a href="https://ncatlab.org/nlab/show/preset">current</a>

   Changed the notation in the example that confused me: added “+” superscripts to the (pre)set symbols.

   diff, v18, current