I first heard it from Fred Brooks in Mythical Man Month. But it's even funnier if it came from Theodore von Karman. A lot of HNers will know him from KSP as the

I first heard it from Fred Brooks in Mythical Man Month. But it's even funnier if it came from Theodore von Karman. A lot of HNers will know him from KSP as the namesake of the Karman line, the boundary between atmosphere and space, typically set at 100km above mean sea level.