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Three U.S. presidents have recognized Ray Kurzweil's contributions: Bill Clinton, George W. Bush, and Barack Obama. Clinton awarded him the National Medal of Technology in 1999, Bush bestowed the National Medal of Science in 2004, and Obama presented him with the Presidential Medal of Freedom in 2013. These prestigious honors underscore Kurzweil's groundbreaking work in artificial intelligence, machine learning, and other fields that have significantly impacted society.