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Topic: Conclusion
Replies: 2   Last Post: Nov 7, 2012 11:46 AM

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Dan Christensen

Posts: 8,219
Registered: 7/9/08
Re: Conclusion
Posted: Nov 7, 2012 11:46 AM
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On Nov 7, 10:08 am, "Jesse F. Hughes" <> wrote:


> Okay, so you're saying that this wasn't an axiomatization of category,
> but simply a question you had about whether this ought to be an
> axiomatization of category?

Yes. In the same posting, I also put forward the idea of an
equivalence relation as an alternative for consideration. In that
case, the comp function would map not to individual morphisms, but to
equivalence classes of morphisms. If I am not mistaken, you yourself
suggested something like that at one point.

> From where I sat, you seemed to be genuinely defending the claim that
> composition is non-functional.

Only in the sense that, in some cases, there are multiple, distinct
candidates for The Composition of two given morphisms as you are
defining a putative comp function for consideration (see my example
with f, g, h1 and h2). To define a suitable comp function, it turns
out that you need only pick one of those alternatives ("Flip a coin").

> Perhaps I was mistaken.  Maybe you were
> playing the Socratic role and not intent on defending your
> non-functional interpretation.
> If so, perhaps the fault is mine, though I doubt it.  You sure looked to
> me like you were seriously suggesting that composition is
> non-functional.  I wonder if others thought the same thing.

I can see where the confusion might arise. And maybe it still exists.

Download my DC Proof 2.0 at

Date Subject Author
Read Re: Conclusion
Jesse F. Hughes
Read Re: Conclusion
Dan Christensen

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