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edits
# Changes

→Nineteenth Century: De Morgan, his laws, and collective/distributive distinction

==== 1854 ====

* English mathematician [[George Boole]] publishes ''The Laws of Thought'', a follow-up to his ''Mathematical Analysis of Logic'' (1847), providing a mathematical basis for [[Aristotelian logic]]. This book introduced [[boolean algebra]] as well as the concept of the "[[universe of discourse]]", although the latter may have been independently formulated by [[Augustus De Morgan]] in 1846.

==== 1860 ====

* British mathematician [[Augustus De Morgan]]'s ''Syllabus of a Proposed System of Logic'' is published. Together with ''Formal Logic'' (1847), this book helped to define [[mathematical logic]] and introduced [[De Morgan's Laws]]. De Morgan also explored the distinction between distributive ("exemplar") and collective ("cumular") predicates.

==== 1879 ====