PREFACE ix

passages from “What is Capital?” 1897, “Senses of
Capital,” 1898, and “The Role of Capital in Economic
Theory,” 1898, and to the Quarterly Journal of Economics
for similar permission with reference to * Precedents for
Defining Capital,” 1904.
I wish also to express my obligations to the many
persons who have aided me in the preparation of this
work, among them especially my wife; my brother, Mr.
Herbert W. Fisher; my colleagues, Professor Henry C.
Emery, Professor John P. Norton, and Dr. Lester W.
Zartman; and my friends, Mr. Richard M. Hurd and
Mr. Orland S. Isbell of New York City.

IRVING FISHER.
New Haven, CoNN., June, 1906.