THE CONCEPTION OF THIS VOLUME This volume, Cardinalism, has been initiated by Ole Hagen, and is now published due to his perseverance and to Kluwer Academic Publishers. Because of various activities and duties, my contribution to the general conception of this volume has only been formal, and all the credit for it is due to Ole Hagen. I should also emphasize that the responsibility for the year's delay in the publishing of this volume is entirely mine, for two reasons. First of all, I have been involved in many works in very different fields. Second, the English translation of my 1943 contribution to the concept of cardinal utility took some time. The points of view the reader will find in this volume are often different and sometimes contradictory, but this can only increase the interest of its reading. In any case, this is not the editors' part to side with or against. Thus contributions to this volume are presented as they have been submit- ted to the editors. Of course, this does not mean that they entirely agree with the analyses presented. MAURICE ALLAIS M. Allais and O. Hagen (eds.), Cardinalism, vii INTRODUCTION Everyone's conscious choices are assumed to reflect their preferences in different situations. For some purposes it serves the theorist's preference for simplicity to assume that a person's life style can be described by the values of some concrete variables, such as quantities of goods available.