Einstein's First Proof http://www.newyorker.com/tech/elements/einsteins-first-proof-pythagorean-theorem?mbid=nl_151119_Daily&CNDID=38409031&spMailingID=8272075&spUserID=MTA3NjEzMTc5MzQ4S0&spJobID=801907437&spReportId=ODAxOTA3NDM3S0
