Dan Van Haften has a B.S. and M.S. in mathematics and a Ph.D. in electrical engineering; he can be reached at dan@thestructureofreason.com. This article is adapted from their book, Abraham Lincoln and the Structure of Reason, which was published by Savas Beatie in hardbound and digital formats and reviewed in the February 2011 issue of The Federal Lawyer. (The authors replied to the review with a letter to the editor in the May 2011 issue of TFL.) In addition to the historical facts contained in the book, the authors reveal how Lincoln tried cases and how he composed his post-1853 speeches. For additional information, see www.thestructureofreason.com. © 2012 by David Hirsch and Dan Van Haften. All rights reserved.