… is from pages 81-82 of Vol. 19 (Ideas, Persons, and Events  ) of The Collected Works of James M. Buchanan ; specifically, it’s from Jim’s 1991 paper “Frank H. Knight,” a remembrance of his great mentor at the University of Chicago:
Frank Knight could never have joined those of the self-selected elite who, in idea or practice, seek to plan, steer, or direct the lives of those who are excluded. He was a classical liberal, not because he predicted that only with widespread individual liberty would desired results be generated, but because the liberal order is required to allow individuals, all individuals, to define their own objectives.
DBx: Neither society in general nor the economy specifically is an engineering project to be ‘maximized,’ ‘optimized,’ or whateverized either by the market’s invisible hand or by the state’s visible fist. And individuals are not fleshy Lego pieces to be assembled or arranged by a giant planner.