As a reader, I never really understood why is it so common for textbooks to have the numbering à la Lemma 9.6. To me it seems to imply that we also have Lemma 9.5 and Lemma 9.7 but sure enough, 9.5 is a definition and 9.7 is an example. So when I started writing my first big assignment, one the first things I googled was how to \swapnumbers.

But unlike the creators of TeX packages and most users of the TeX.SE, I know little to nothing about typesetting. So I assume that the default option wasn't chosen randomly and would be happy to know the reason and maybe become convinced that Lemma 9.6 is the way to go.

Update: just to clarify, I meant why

Definition 9.5

Lemma 9.6

Example 9.7

as opposed to

9.5 Definition

9.6 Lemma

9.7 Example

So I'm not questioning the unified numbering (which it a good thing beyond any doubt).

  • For that you can use ntheorem.
    – Bernard
    Commented Jul 29, 2014 at 19:19
  • 1
    Because if you refer to it, it's weird to say As we derived in 9.6 Lemma. And if you are searching for a lemma 9.6, it's a royal pain in the ass, if every kind is numbered on its own. Then definition 9.9 comes after lemma 9.3 and you have to check every page to catch it. But I share your bitterness, I think this stuff is archaic and we need to get a better way of it. I am not quite sure what.
    – percusse
    Commented Jul 29, 2014 at 19:19
  • It mostly depends on what you are thinking to be numbering: if you're numbering paragraphs (à la française), then the number goes first; if you're numbering the statements, then the number goes second.
    – egreg
    Commented Jul 29, 2014 at 19:21
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    I guess 'off topic', but in English 'Lemma 9.6' makes sense whereas '9.6 Lemma' doesn't as a 'name'. Note that it's the same for something where the numbers do run through: 'Section 1', 'Section 2', etc. and not '1 Section'.
    – Joseph Wright
    Commented Jul 29, 2014 at 19:44
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    @percusse: cleveref could handle this case intelligently, I think.
    – Bernard
    Commented Jul 29, 2014 at 21:54


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