When you try to start some talk about permanent transformation, but you accidentally do it from your mathstodon.xyz account, so it comes out as a lemma about matrices.
(There is an audience for this joke and I believe it's exactly 'me'.)
@Austin_Dern I think I attempted to do similar jokes when I turned people down for roleplay because my Linear Algebra homework wasn't done.
@NovaSquirrel Heh!