From PBS.org: http://www.pbs.org/teachers/mathline/concepts/president/activity2.shtm There are many proofs to the Pythagorean theorem. President James Garfield developed his own proof in The Journal of Education (Volume 3 issue161) in 1876. President Garfield studied math at Williams College (in Williamstown, MA) and taught in the public school in Pownal, Vermont, for a year or two after graduating. President Garfield may have been joking when he stated about his proof that, "we think it something on which the members of both houses can unite without distinction of the party." A nice feature of mathematical proofs is that they are not subject to political opinion. COMMENT: This site doesn't actually make the proof explicit -- it's more a series of hints -- though you can find details at MathWorld below. It involves computing the area of a cleverly constructed trapezoid based on the original right triangle. Garfield didn't really create the theorem (known since antiquity) but he discovered a new kind of proof. And he did it BEFORE he was president, if that matters? For details see MathWorld.com -- Pythagorean Theorem http://mathworld.wolfram.com/PythagoreanTheorem.html A novel proof using a trapezoid was discovered by James Garfield (1876), later president of the United States, while serving in the House of Representatives