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Topic: Conclusion
Replies: 2   Last Post: Nov 7, 2012 9:09 AM

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Dan Christensen

Posts: 8,219
Registered: 7/9/08
Re: Conclusion
Posted: Nov 7, 2012 9:09 AM
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On Nov 7, 6:53 am, "Jesse F. Hughes" <> wrote:
> Dan Christensen <> writes:
> > On Nov 6, 6:18 pm, "Jesse F. Hughes" <> wrote:
> >> You didn't say that.  You said earlier today that composition was not
> >> functional.

> > [snip]
> > Pay attention, Jesse. In every version of my definition of category,
> > composition was presented as a function. For every ordered pair of
> > compatible morphisms, there would exist a unique morphism that was
> > their composition. After posting my latest version, I began to openly
> > question it here, wondering if indeed such a unique morphism always
> > existed. It doesn't always, but, as Aatu pointed out in effect, you
> > arbitrarily pick one of the alternatives for your definition of
> > compositions to maintain functionality -- "We flip a coin." So, my
> > latest definition of stood.

> Wow.  You are either a liar or have a mental condition that represses
> all memory of your errors.
> Look at message
> Message-ID: <>
> Here, we find axiom 2:
> 2  ALL(f):ALL(g):ALL(h):[f @ mor & g @ mor & h @ mor => [(f,g,h) @
> comp
>    <=> cod(f)=dom(g) & dom(f)=dom(h) & cod(h)=cod(g)]]

A little creative editing, Jesse? In the text just prior to that (see
link), I wrote:

"I also think there may be a larger problem with the functionality of
composition. Suppose, for example, that f is morphism from object A to
object B, that g is morphism from B to C, and that h1 and h2 are
distinct morphisms from A to C. Then comp(g,f) as defined here could
be either h1 or h2, could it not? Should we define some equivalence
relation on mor. Should comp be seen as a non-functional mapping from
mor x mor to mor? How about something like..."

Aatu, it seems, kicked your ill-informed butt with his "We flip a
coin" remark. You no longer claim I was "lying" about that. That's
real progress. But here, it seems you are reduced to deliberately
taking my words out of context and, again, calling me a liar!

In your desperate, never-ending attempts to make me look stupid, it
seems to have backfired on you, Jesse.

Now, about those massive insecurities....

Download my DC Proof 2.0 software at

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

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