--- Unknown; many attributions
Miller & Page in their Complex Adaptive Systems (2007) p. 6 cite Paul Samuelson using it to describe economics, citing Samuelson's foreword in Michael Salzberg, Passion and Craft: Economists at work, Ann Arbor: University of Michigan Press (1999)
Paul H. Smith in Reading the Enemy's Mind (2005) mentions Max Planck, Niels Bohr and Max Born (without attribution).
