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    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeApr 15th 2010
    • (edited Apr 15th 2010)

    I gave regular cardinal its own page.

    Because I am envisioning readers who know the basic concept of a cardinal, but might forget what “regular” means when they learn, say, about locally representable category. Formerly the Lab would just have pointed them to a long entry cardinal on cardinals in general, where the one-line definition they would be looking for was hidden somewhere. Now instead the link goes to a page where the definition is the first sentence.

    Looks better to me, but let me know what you think.

    • CommentRowNumber2.
    • CommentAuthorHarry Gindi
    • CommentTimeApr 15th 2010
    • (edited Apr 15th 2010)

    I agree. These are the kinds of little changes that greatly improve readability! =)

    • CommentRowNumber3.
    • CommentAuthorUrs
    • CommentTimeApr 15th 2010

    I agree. These are the kinds of little changes that greatly improve readability! =)

    Okay, good. I have kept the stuff on regular cardinals at cardinal by the way. Because we also had the complaint that too many entries are not self-contained enough. It can be a difficult design decision.

    • CommentRowNumber4.
    • CommentAuthorHarry Gindi
    • CommentTimeApr 15th 2010
    • (edited Apr 15th 2010)

    Redundancy is not a priori a bad thing. What would be bad is if the entries contradicted each other. “Recalling” the definition is often helpful, especially for a work like the nLab.

    • CommentRowNumber5.
    • CommentAuthorUrs
    • CommentTimeApr 15th 2010
    • (edited Apr 15th 2010)

    Redundancy is not a priori a bad thing. […] “Recalling” the definition is often helpful, especially for a work like the nLab.

    What troubles me is that with whole chunks of material duplicated, all further changes/imrpovements/additions/corrections would need to by done twice and harmonized. That goes against the whole wiki-spirit.

    I suppose there should be automated solutions, where one uses an include command to include the content of one entry into another. But then the indluded content needs to b prepared, suitably, for instance in not having its own TOC and things like that. Can get messy.

    • CommentRowNumber6.
    • CommentAuthorDavidRoberts
    • CommentTimeApr 15th 2010
    • (edited Apr 15th 2010)

    From regular cardinal:

    because a set with cardinality less than aleph-1 is a finite set

    which is clearly false :) Friendly lab elf, please bypass the spam filter on my behalf and fix this by replacing this with aleph-0 :)

    • CommentRowNumber7.
    • CommentAuthorAndrew Stacey
    • CommentTimeApr 15th 2010

    The way to address the problem that Urs and Harry were discussing is with use of the !include directive. If the "regular cardinal" section of "cardinal" is truly to be a copy of the content at "regular cardinal", then make it so by putting [[!include regular cardinal]] at the correct point.

    (Yay! I managed to type that without using any funny entities for the square brackets.)

    • CommentRowNumber8.
    • CommentAuthorMike Shulman
    • CommentTimeApr 15th 2010
    • (edited Apr 15th 2010)

    I don’t think the text about regular cardinals at cardinal should be the same as (e.g. !included from) regular cardinal. The latter can be arbitrarily detailed, whereas at the former we are mentioning it only as one of many properties of cardinals and thus should not spend a huge amount of time on it. I’m not extremely bothered about the “duplication” here, because it doesn’t seem to me that there should ever be very much content at cardinal to duplicate; most new content should be added to regular cardinal. If the definition of regular cardinal ever changed, then we’d have to change it in both places, but that seems unlikely.

    • CommentRowNumber9.
    • CommentAuthorMike Shulman
    • CommentTimeApr 15th 2010

    Is there any reason you chose π\pi to denote the regular cardinal at regular cardinal? Usually cardinals are denoted by κ\kappa

    • CommentRowNumber10.
    • CommentAuthorHarry Gindi
    • CommentTimeApr 15th 2010

    Yes, pi is definitely an overloaded letter.

    • CommentRowNumber11.
    • CommentAuthorUrs
    • CommentTimeApr 15th 2010

    Is there any reason you chose π\pi to denote the regular cardinal at regular cardinal?

    This was copy-and-pasted from cardinal. I don’t recall who made that choice there, and for what reason.

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