1989, Richard Schechner, "Race Free, Gender Free, Body-Type Free, Age Free Casting," TDR, vol. 33, no. 1 (Spring), p. 6, Even scientific propositions regarding entities like "strange attractors" or "quarks" are not understood by many people—and are accepted as real only when these abstruse ideas, often enunciable only as mathematical equations, have been translated into "practical results."
Source: wiktionary