FOM: typo in categorical foundations

Colin Mclarty cxm7 at
Wed Nov 19 09:57:39 EST 1997

	I'll reply to Torkel's and Vaughn's comments later today, but

Reply to message from torkel at of Wed, 19 Nov

>(There seems to be a typo in your
>presentation, since your axiom C1 is a logical truth.)

	Yes. C1 as written there repeats the definition just before it:
u is an "identity arrow" iff whenever a composite fu is defined, then
fu=f. C1 should have been the dual to this: Whenever a composite ug
is defined, then ug=g.

Colin McLarty

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