An Investigation of the Laws of Thought by George Boole
= An Investigation of the Laws of Thought by George Boole
{c}
{tag=Work by George Boole}
{title2=1854}
Primary text, Chapters II–III, on the meaning and laws of class symbols, including $x^2=x$. Its operations and restrictions should be distinguished from a modern <Boolean algebra>.
Online source: https://www.gutenberg.org/files/15114/15114-pdf.pdf