A Treatise on the Family GARY S. BECKER A Treatise on the Family ENLARGED EDITION Harvard University Press Cambridge, Massachusetts London, England Copyright © 1981, 1991 by the Presidentand FellowsofHarvardCollege All rights reserved Printed in the United StatesofAmerica This book has been digitallyreprinted. Thecontent remains identicaltothatofprevious printings. FirstHarvard UniversityPresspaperbackedition, 1993 LibraryofCongress Cataloging-in-Publication Data Becker,Gary Stanley, 1930- Atreatise on thefamily /Gary S. Becker. - Enl. ed. p. em. Includes bibliographicalreferences(p. Includes index. ISBN0-674-90698-5(acid-freepaper)(cloth) ISBN0-674-90699-3 (paper) 1. Family-Economicaspects. I. Title. HQ518.B35 1991 90-4975 306.85-dc20 CIP To Guity for support and confidence when progress was slow Contents Preface to the Enlarged Edition ix Introduction 1 1 Single-Person Households 20 2 Division of Labor in Households and Families 30 Supplement: Human Capital, Effort, and the Sexual Division ofLabor 54 3 Polygamy and Monogamy in Marriage Markets 80 4 Assortative Mating in Marriage Markets 108 5 The Demand for Children 135 Supplement: A Reformulation ofthe Economic Theory ofFertility 155 6 Family Background and the Opportunities of Children 179 7 Inequality and Intergenerational Mobility 201 Supplement: Human Capital and the Rise and Fall ofFamilies 238 8 Altruism in the Family 277 9 Families in Nonhuman Species 307 viii ] Contents 10 Imperfect Information, Marriage, and Divorce 324 11 The Evolution ofthe Family 342 Supplement: The Family and the State 362 Bibliography 383 Index 411 Preface to the Enlarged Edition In this book I develop an economic orrational choice approach to the family. The title does not refer to economic aspects of the family, however, because most noneconomists and many economists would interpret the qualifier "economic" to indicate that the discussion is confinedto the materialaspectsoffamily life, to incomes and spending patterns. My intent is more ambitious: to analyze marriage, births, divorce, division oflabor in households, prestige, and other nonmate rial behavior with the tools and framework developed for material behavior. That is to say, this book contains an economic approach to the family, not in the sense ofan emphasis on the material aspects of family life, butinthe senseofachoice-theoreticframeworkforanalyz ing many aspects offamily life. The rational choice approach has been refined during the past two hundred years. It now assumes that individuals maximize their utility from basic preferences that do not change rapidly over time, and that the behavior of different individuals is coordinated by explicit and implicit markets. I argued in an earlier publication that the economic approach is not restricted to material goods and wants or to markets with monetary transactions, and conceptually does not distinguish be- ix