 : B x B -&gt; B,
along with the whole stock of 2-adic relations previously granted.
Then one tries to see what other 3-adics can be generated from these
augmented resources.  The ones that can be so produced are reducible
over this resource base;  the ones that can't be so constructed are
then called &quot;irreducible&quot; in a stronger sense, the genuine 3-adics.
At any rate, this seems to fit the examples that Peirce provides.

I am putting a detailed &quot;work in progress&quot; on these issues here:

