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Francois Ziegler
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As basic hygiene, please state theorems before, not after their proofs. I find nothing more annoying than the style where some seemingly random agitation is followed by

... and therefore we have proved:

Theorem 3.47 Let a regular gizmo have transversality property (3.25). Then the closed sub-gizmo (3.20) has property (3.30).

The problem with such a structure is that it may in fact be impossible to rewrite in the normal theorem-proof order, because only after half the proof does "(3.20)" turn out to be well-defined, let alone closed; or properties "(3.25)" and "(3.30)" may be impossible to even state outside the context of the proof, e.g. because they involve auxiliary objects whose existence was not assured a priori.

So instead, 1º) set up the minimal environment where the result may be meaningfully stated; then 2º) state and 3º) prove it. Or at least, make sure that this could be done.

Francois Ziegler
  • 31.5k
  • 6
  • 121
  • 176