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Category Theory Illustrated – Orders

by boris_m on 4/18/2026, 6:40:47 AM

https://abuseofnotation.github.io/category-theory-illustrated/04_order/

Comments

by: dgan

I think it is pretty obvious that at the challenge with all abstract mathematics in general and the category theory in particular isnt the fact that people dont understand what a "linear order" is, but the fact it is so distant from daily routine that it seems completely pointless. It's like pouring water over pefectly smooth glass

4/18/2026, 8:00:59 AM


by: arketyp

There is a way to frame category theory such that <i>it&#x27;s all just arrows</i> -- by associating the identity arrow (which all objects have by definition) with the object itself. In a sense, the object is syntactic sugar.

4/18/2026, 7:59:11 AM


by:

4/18/2026, 8:22:55 AM


by: gobdovan

Unless there&#x27;s some idiosyncratic meaning for the `=&gt;`, the Antisymmetry one basically says `Orange -&gt; Yellow =&gt; Yellow -&#x2F;&gt; Orange`. The diagram is not acurate. The prose is very imprecise. &quot;It also means that no ties are permitted - either I am better than my grandmother at soccer or she is better at it than me.&quot; NO. Antisymmetry doesn&#x27;t exclude `x = y`. Ties are permitted in the equality case. Antisymmetry for a non-strict order says that if both directions hold, the two elements must in fact be the same element. The author is describing strict comparison or total comparability intuition, not antisymmetry.

4/18/2026, 8:26:05 AM


by: somewhereoutth

The first 90% of this is standard set theory.<p>I&#x27;m unclear what the last 10% of &#x27;category theory&#x27; gives us.

4/18/2026, 8:41:46 AM