aware of:  an algebraic notation and
&gt; a graph notation can have identical expressive power.  Just getting
&gt; that point through their pointy little heads is a major victory.
&gt; And until you drive that point home, you can't even get their
&gt; attention on any more substantive issue.
&gt; 
&gt;  &gt; A hundred years of wasted time and effort have shown it.
&gt;  &gt; There is no choice but going back to the viable sources,
&gt;  &gt; of which Peirce provides us with just one of several.
&gt; 
&gt; I