I guess it wouldn't hurt to compare Tom's discovery with that of George J. Friedman in the 1968 period, Frege in the late 19th century, Harary in the 1960s, etc., etc.

May I also recommend highly the book by the late Father I. M. "Joseph Bochenski" titled "A History of Formal Logic".  Having studied virtually of the philosophers from Zeno (400 BC) onward to about 1930, demonstrating portions of their writings, interpreting them for the informed lay reader, showing how Leibniz was using "Venn Diagrams" more than a hundred years before Venn, etc., commenting on Frege's invention of graphic portrayals of logic, etc., etc., it helps us all to begin to be oriented in a broader framework.

John N. Warfield