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Vanilla 1.1.10 is a product of Lussumo. More Information: Documentation, Community Support.
Added a proof of the pasting lemma to pullback, and the corresponding lemma to comma object (also added the construction by pullbacks and cotensors there).
A --> B --> C
| | |
v v v
D --> E --> F
A ==== A ==== A
| | |
| |i |
| v |
A ---> B ---> A
i p
Well spotted. The mistake in the ’proof’ is in confusing cones over $(d \to e \to f, c \to f)$ and cones over $(d \to e, e \to f, c \to f)$. I think they are the same iff the right square is a pullback.
Edit: I made the same mistake at comma object. Both fixed now, I think.
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