The papers of Jacob Marschak which follow in these volumes are an extraordinary combination of original and fruitful departures in economic and social thought, superb clarity of exposition, and sensitivity to the values of earlier work and even competing traditions. They make us marvel alike at their variety, their quantity, and their quality. But they do not, even so, fully reflect Marschak's contributions to the development of social science. He has had an unusual influence as one who exercises leadership. In a formal, organizational sense, this role has been manifest in his capacity as...