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Vanilla 1.1.10 is a product of Lussumo. More Information: Documentation, Community Support.

• CommentRowNumber1.
• CommentAuthorUrs
• CommentTimeFeb 24th 2010

Added an "Examples"-section to well-pointed topos and to Boolean topos mentioning Set and models for ETCS.

• CommentRowNumber2.
• CommentAuthorUrs
• CommentTimeFeb 24th 2010

started a section well-pointed (oo,1)-topos as parts of the blog discussion here

In the course of that I added to the plain definition the statement that the global section functor is faithful

• CommentRowNumber3.
• CommentAuthorNikolajK
• CommentTimeSep 12th 2020

The pretopos section ends in a sentence I don’t know how to interpret:

But of course it applies whenever one is studying a pretopos.

Does this really mean topos here at the end? If not, what is “it”?

• CommentRowNumber4.
• CommentAuthorDavidRoberts
• CommentTimeSep 12th 2020

I think the “it” means this bit:

we have to strengthen the condition that 1 is a generator to the condition that 1 is a strong generator,

And I think the “whenever” means that it’s not just in thinking about a predicative category of sets, but an arbitrary pretopos.

• CommentRowNumber5.
• CommentAuthorDavidRoberts
• CommentTimeSep 12th 2020

Clarified last paragraph of the section “In a pretopos”

• CommentRowNumber6.
• CommentAuthorMike Shulman
• CommentTimeMar 4th 2021

Fixed the last equivalent version of well-pointedness, and added a proof that 1 is also a strong generator.

• CommentRowNumber7.
• CommentAuthorMike Shulman
• CommentTimeMar 4th 2021

Added a proof that in classical logic, well-pointedness is equivalent to the conjunction nondegenerate + Boolean + two-valued + split supports. This seems to be hard to find in the literature.

• CommentRowNumber8.
• CommentAuthorKeith Harbaugh
• CommentTimeMar 4th 2021

Added section “References”, at this time containing only some references to Mac Lane and Moerdijk’s SGL. Also added some remarks.

• CommentRowNumber9.
• CommentAuthorMike Shulman
• CommentTimeMar 5th 2021

Added citations for the recently added theorem, thanks to an anonymous contributor by email.