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Stream: deprecated: mathematics

Topic: What is trivial


view this post on Zulip Amar Hadzihasanovic (Feb 11 2021 at 13:36):

I like the opening to George M. Bergman's 1978 paper, The diamond lemma for ring theory:

The main results in this paper are trivial. But what is trivial when described in the abstract can be far from clear in the context of a complicated situation where it is needed.

It's in a paper on algebra but I think it captures some of the culture of CT.

view this post on Zulip Fawzi Hreiki (Feb 11 2021 at 14:04):

Amar Hadzihasanovic said:

It's in a paper on algebra but I think it captures some of the culture of CT.

Well category theory is algebra - namely, the algebra of composition.

view this post on Zulip Mike Shulman (Feb 11 2021 at 14:07):

Reminds me of Peter Freyd's famous remark that "perhaps the purpose of categorical algebra is to make that which is trivial, trivially trivial."

view this post on Zulip Fawzi Hreiki (Feb 11 2021 at 14:11):

It can be a bit misleading though for that to be viewed as the sole purpose of category theory (not that the quote says that). I think, and I imagine many here do too, that category theory has its own internal aesthetic which is worth studying in the same way that group theory or algebraic geometry is worth studying.

view this post on Zulip Mike Shulman (Feb 11 2021 at 16:38):

Yes, there are many misleading things about that quote. Peter May once suggested that it might be better to say "to make that which is formal, formally formal", since something can be formal without being trivial.

view this post on Zulip Nathanael Arkor (Feb 11 2021 at 16:39):

Perhaps "that which is trivial, formally trivial" also captures the intent better.

view this post on Zulip Nathanael Arkor (Feb 11 2021 at 16:40):

But it's less amusing that way.

view this post on Zulip John Baez (Feb 11 2021 at 16:49):

Mike Shulman said:

Reminds me of Peter Freyd's famous remark that "perhaps the purpose of categorical algebra is to make that which is trivial, trivially trivial."

Reminds me of how when I told Timothy Gowers this, he said something like "For me it's enough that it be trivial".

view this post on Zulip Jason Erbele (Feb 11 2021 at 19:25):

Is there an n-trivialty hierarchy like there is an n-category hierarchy? Perhaps "nontrivial" = (-1)-trivial, "trivial" = 0-trivial, "trivially trivial" = 1-trivial…

view this post on Zulip John Baez (Feb 11 2021 at 19:32):

There is such a hierarchy, but it gets nontrivial when we reach inaccessible cardinals.

view this post on Zulip Jason Erbele (Feb 11 2021 at 19:34):

Sorry – can't resist. Going any further than trivially trivial according to my proposed numbering of the hierarchy might be too trivial (2-trivial). :sunglasses:

view this post on Zulip Todd Trimble (Feb 12 2021 at 01:16):

Nathanael Arkor said:

Perhaps "that which is trivial, formally trivial" also captures the intent better.

Wait, are you just pretending not to know May's version? "That which is formal, is formally formal".

view this post on Zulip Joe Moeller (Feb 12 2021 at 01:18):

No, Mike said that right before.

view this post on Zulip Todd Trimble (Feb 12 2021 at 01:24):

So he did.