Paul Samuelson (the first American Nobel Laureate in Economics, and arguably the most influential economist of the 20th century) died today at home at age 94. He was largely responsible for the transformation of economics from a largely descriptive and discursive discipline to a highly mathematical and rigorous one.
He was responsible for turning MIT into a world-class economics center - over the years, he played a role in bringing in Solow, Engle, Klein, Krugman, Modigliani, Merton, and Stiglitz.
In addition, he wrote perhaps the single most popular and widely used economics text in history - "Economics", published in 1948. I read it in my undergraduate years in the late 1970s, and it was still selling 50,000 copies a year in the late 1980s.
A giant has passed.