Is my 'proof' that any strict total order is not total correct?

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I am wondering whether a strict total order is total.

As I understand it, a strict total order is (among other things) irreflexive.

But for a relation $R$ to be total, it needs to be true that for any $a$ and $b$; either $aRb$ or $bRa$.

So, if we pick $a=b$, then we must have $aRa$ for any $a$ for it to be total, making it reflexive, rather than irreflexive.

So, it seems that every strict total order is not total.

Is this correct? It seems ... counterintuitive ...

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You are quoting the condition of "total" wrong, for strict orders. For the strict order we require the trichotomy law to be:

For all $a,b$ either $a<b$ or $b<a$ or $a=b$.

The last option happens automatically in the non-strict version, as you said, due to reflexitivity. But on the other hand, anti-symmetry is easier to formulate for strict orders (and in fact follows from irreflexivity and transitivity).