As the NBER web site points out, February 12 is the birthday of economists Eugen Bohm-Bawerk and Julian Simon. Here is the bio of Bohm-Bawerk in The Concise Encyclopedia of Economics. One highlight from that bio:
Böhm-Bawerk was also one of the first economists to discuss Karl Marx's views seriously. He argued that interest does not exist due to exploitation of workers. Workers would get the whole of what they helped produce only if production were instantaneous. But because production is roundabout, he wrote, some of the product that Marx attributed to workers must go to finance this roundaboutness, that is, must go to capital. Böhm-Bawerk noted that interest would have to be paid no matter who owned the capital. Mainstream economists still accept this argument.
Interestingly, the late Paul Samuelson, in a footnote in his obituary of Bertil Ohlin, argued that if the Nobel prize for economics had been offered as early as the other Nobel prizes, Bohm-Bawerk would likely have been its first recipient.
Julian Simon died in 1998, just shy of his 66th birthday. Here's a key excerpt from Wikipedia about his work:
He is best known for his work on population, natural resources, and immigration. His work covers cornucopian views on lasting economic benefits from natural resources and continuous population growth, even despite limited or finite physical resources, empowered by human ingenuity, substitutes, and technological progress.
In The Population Bomb, Mr. [Paul] Ehrlich generalized from animal behavior--he had studied butterflies--to human behavior. But Simon saw humans as fundamentally different from animals. He liked to quote the 19th-century American economist Henry George: "Both the jayhawk and the man eat chickens, but the more jayhawks, the fewer chickens, while the more men, the more chickens."