view wisdom/categorical product @ 11288:9613519b554c

<int-e> learn 8/8/8/8/8/8/8/8 is an empty chess board in FEN notation.
author HackBot
date Sat, 30 Dec 2017 16:57:14 +0000
parents 00af4aaadf2c
children
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categorical product is like when you have two category elements A and B then their product is element C iff there are two morphisms p:C->A and q:C->B such that for every element X and morphisms u:X->A and v:X->B there is a unique morphism w:X->C such that u=wp and v=wq.