 In late 1847, Boole and Augustus De Morgan (1806–1871) each published a book on logic—Boole’s Mathematical Analysis of Logic (1847) and De Morgan’s Formal Logic (1847). De Morgan’s approach was to dissect every aspect of traditional deductive logic (usually called ‘Aristotelian logic’) into its minutest components, to consider ways to generalize these components, and then, in some cases, undertake to build a logical system using these components. Unfortunately, he was never able to incorporate his best ideas into a significant system. His omission of a symbol for equality made it impossible to develop an equational algebra of logic. It seems that synthesis was not De Morgan’s strong suit.