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1. • CommentRowNumber1.
   • CommentAuthorOscar_Cunningham
   • CommentTimeJun 14th 2017
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   Author: Oscar_Cunningham
   Format: MarkdownItexTodd has a "do not tamper" request up on [the page](https://ncatlab.org/nlab/show/graph+minor) at the moment, so I haven't actually added this (and perhaps Todd intends to add precisely what I am about to say) but I think that the page needs to mention and prove the following remark: that the graph minors of $G$ are precisely the graphs $H$ such that there exists a monomorphic functor $\Pi_1 H\to\Pi_1 G$, where $\Pi_1$ is the "groupoid of paths" functor.

   Todd has a “do not tamper” request up on the page at the moment, so I haven’t actually added this (and perhaps Todd intends to add precisely what I am about to say) but I think that the page needs to mention and prove the following remark: that the graph minors of $G$ are precisely the graphs $H$ such that there exists a monomorphic functor $\Pi_1 H\to\Pi_1 G$, where $\Pi_1$ is the “groupoid of paths” functor.

2. • CommentRowNumber2.
   • CommentAuthorTodd_Trimble
   • CommentTimeJun 14th 2017
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   Author: Todd_Trimble
   Format: MarkdownItexI haven't thought about that. Do you have a proof in mind? Would you like to amplify on "needs to"?

   I haven’t thought about that. Do you have a proof in mind? Would you like to amplify on “needs to”?

3. • CommentRowNumber3.
   • CommentAuthorTodd_Trimble
   • CommentTimeJul 31st 2023
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   Author: Todd_Trimble
   Format: MarkdownItexI removed the "do not tamper" request.

   I removed the “do not tamper” request.