Re: terminology

["Joyal, André" <joyal.andre@uqam.ca>]

Dear Ronnie,

I totally agree with what you wrote.

I wrote 

------------------------------------------------------------
One lies in the fact that equivalent categories are considered 
to be the "same",
------------------------------------------------------------- 


I was careful not to write

------------------------------------------------------------
One lies in the fact that equivalent categories are considered 
to be the same,
------------------------------------------------------------- 

Sorry for not been clear enough.
I hope this settle our apparent disagreement.

Best,
André




-------- Message d'origine--------
De: Ronnie Brown [mailto:ronnie.profbrown@btinternet.com]
Date: sam. 22/05/2010 17:43
À: Joyal, André
Cc: Urs Schreiber; categories@mta.ca
Objet : Re: RE : categories: Re terminology:
 
Dear André

There seems to me to be a tremendous amount of great work going on 
higher category theory, but when you write

-----------------------------------------------------
One lies in the fact that equivalent categories are considered to be the 
"same", 

even if [or] when they are not isomorphic.
-----------------------------------------

this seems to go against the grain of what I have been doing in groupoids since I decided they were valuable in about 1965! It sounds like the old canard `groupoids reduce to groups', so there must be some confusion in my mind on what you are saying. 


....



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