George Spencer-Brown in his cryptic book, Laws of Form, started off reasoning about “the Distinction” and ended up with an algebra that later writers showed to be the Boolean algebra of two elements. This strange outcome can be accounted for by the fact that the BA of two elements, i.e., the powerset BA of the one element set, with all the usual subset operations is isomorphic to the partition algebra of partitions on the two element set using the partition operations. Partitions are about making distinctions so “the Distinction” is the act of distinguishing the two elements. This is further explained in the note that can be downloaded.