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1. • CommentRowNumber1.
   • CommentAuthorjesuslop
   • CommentTimeNov 11th 2017
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   Author: jesuslop
   Format: MarkdownItexHi, correct me if wrong but when learning about the [Category of Elements](https://ncatlab.org/nlab/show/category+of+elements), I think the projection is in reality a (discrete) op-fibration instead of a fibration. It's the *outgoing* morphisms from the base of the fiber that are lifted.

   Hi, correct me if wrong but when learning about the Category of Elements, I think the projection is in reality a (discrete) op-fibration instead of a fibration. It’s the outgoing morphisms from the base of the fiber that are lifted.

2. • CommentRowNumber2.
   • CommentAuthorMike Shulman
   • CommentTimeNov 12th 2017
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   Author: Mike Shulman
   Format: MarkdownItexAh, yes, the idea section is mixing up the category of elements of a covariant functor (which is a discrete opfibration) with that of a contravariant functor (which is a discrete fibration).

   Ah, yes, the idea section is mixing up the category of elements of a covariant functor (which is a discrete opfibration) with that of a contravariant functor (which is a discrete fibration).

3. • CommentRowNumber3.
   • CommentAuthorMike Shulman
   • CommentTimeNov 13th 2017
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   Author: Mike Shulman
   Format: MarkdownItexFixed there. Did you see it anywhere else?

   Fixed there. Did you see it anywhere else?

4. • CommentRowNumber4.
   • CommentAuthorjesuslop
   • CommentTimeNov 13th 2017
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   Author: jesuslop
   Format: MarkdownItexThanks! No that I know of.

   Thanks! No that I know of.