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Figure 1. Title page of the 1811 edition of William Duncan's Elements of Logic, originally published in 1748
William Duncan (1711-1760) was a Scottish philosopher and Professor of Natural Science at Marischal College, Aberdeen, Scotland. In 1748 he published The Elements of Logic in Four Volumes, which became a popular text on the discipline of logic. This work was adopted in the early colleges of America. Thomas Jefferson, when he studied at William and Mary College (1760-1762), used Duncan’s Logic and later retained a copy of the work in his personal library. It is believed that its instruction may have influenced the composition of the Declaration of Independence (Golden & Golden, p. 47). The title page for the 1811 edition is shown above.
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Figure 2. On page 143, Duncan considered the moral implications of argumentation.
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Figure 3. Here on page 207 the author endorsed the study of algebra as a means to strengthen one's ability to think logically.
Reference
James Golden and Alan Golden, Thomas Jefferson and the Rhetoric of Virtue, Rowan & Littlefield, Landen, Maryland, 2002.
Acknowledgment
These images are presented courtesy of Archives and Special Collections, Dickinson College, Carlisle, Pennsylvania. You may use them in your classroom and/or for private study. For all other purposes, please obtain permission from Archives and Special Collections, Waidner-Spahr Library, Dickinson College, Carlisle, PA.