Abraham Lincoln rose from a nearly non-existent formal education to become the 16th President of the United States. In a brief biography provided to friends endorsing his 1860 nomination he wrote “I could read, write, and cipher to the Rule of Three; but that was all.” That was the extent of his formal schooling.

Page from Lincoln’ sum book. Photo courtesy Library of Congress.
Anyone with an interest in Lincoln – or frontier schooling in general – has likely heard those words, but very few people probably know what they mean. The reading and writing make sense, but “ciphering to the rule of three?”
It turns out the “rule of three” is a way of solving proportions, what we more commonly today call “ratios.” It is a form of cross-multiplication in which the problem is set up such that the unknown quantity is the last “extreme” in a series of numbers exhibiting a proportional relationship. The basic form is:

The idea is to determine the value of x when you know the values of a, b, and c. The Rule of Three states that you simply rearrange this simple ratio formula into:

Another way of looking at it is by laying out the three known terms in a linear sequence (a –> b –> c) and then multiplying the last term (c) by the middle term (b) and then dividing that product by the first term (a).
That’s it. Not very complicated on its face, but this simple rule could incorporate not only multiplication and division but also addition and subtraction. Lincoln likely used it to figure out proportions and costs for different supplies during the time he was a young storekeeper in New Salem. Of course, Lincoln went on to learn long division and other math functions as well, not to mention he mastered the six books of Euclid geometry. He also taught himself the law, political oratory, and the logical thinking that helped him define the slavery debate and, eventually, make him one of our greatest presidents.
Not bad for a guy with less than a year of formal schooling.
[The above is adapted from my book, Lincoln: The Fire of Genius and an article published in The Lincolnian, a publication of the Lincoln Group of the District of Columbia.]

Lincoln: The Fire of Genius: How Abraham Lincoln’s Commitment to Science and Technology Helped Modernize America is available at booksellers nationwide.
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David J. Kent is President of the Lincoln Group of DC and the author of Lincoln: The Fire of Genius: How Abraham Lincoln’s Commitment to Science and Technology Helped Modernize America and Lincoln: The Man Who Saved America.
His previous books include Tesla: The Wizard of Electricity and Edison: The Inventor of the Modern World and two specialty e-books: Nikola Tesla: Renewable Energy Ahead of Its Time and Abraham Lincoln and Nikola Tesla: Connected by Fate.
Author Chris DeRose takes a more detailed look at a period in Abraham Lincoln’s life that is normally glossed over in other biographies – his single term as a U.S. Congressman. The first few chapters highlight the political status of the time, as well as the political wrangling between different factions both within and external to the Whig party. The book goes into various aspects of the key question of the day, slavery. Doing so makes it clear that the post-Civil War reinvention of history to suggest the South wasn’t fighting to maintain and expand slavery is hogwash.
The title comes from the controversy (assuming you knew there was a controversy) over whether Edwin Stanton, upon Lincoln taking his last breath, said “Now he belongs to the ages” or “Now he belongs to the angels.” With this contrivance as a starting point Gopnik presents what amounts to six essays.
Abraham Lincoln is the only president to ever get a patent, an ingenious, though impractical, method for lifting boats over shoals. This interest in technology served him well during the Civil War as battles increasingly relied on mechanization for transportation, communication, and weaponry.
Abraham Lincoln’s Air Force – Balloons in the Civil War
Abraham Lincoln and the Technology of War


The world woke up this morning to the news of the untimely death of actor, comedian, and humanitarian Robin Williams. Having been a fan of his since his first appearance as Mork on the sitcom Happy Days, before he spun the character off into his own show Mork and Mindy, his demise comes as a shock. The world mourns.
Abraham Lincoln and Charles Darwin were born on the same day, February 12, 1809. Both became icons of change and are will be remembered throughout history for their contributions. The book is subtitled: Shared Visions of Race, Science and Religion. While their views were not so much shared as contrasted, author James Lander deftly flips back and forth between Darwin’s and Lincoln’s lives as they experience their separate travels, coming of age, development of ideas, and eventual breakthroughs into the public eye as they dramatically change history.
Everyone knows Abraham Lincoln, in part because of the diligent work done by his two secretaries – John G. Nicolay and John Hay. But little has been done to illuminate the two men themselves. Zeitz has done us all a favor by accomplishing just that.







