“The nature of wealth and value is explained by the consideration of an infinitely small amount of pleasure and pain, just as the theory of statics is made to rest upon the equality of indefinitely small amounts of energy. (Jevons, 1879, p. 44; Italics, added)”
Standard economic theory takes individual preferences as given and fixed over the course of the individual's lifetime. It would be hard to imagine how economic models can stand still by giving up preferences or utility functions. They serve as the very foundation of economics just as we quoted above from William Stanley Jevons (1835-1882). Without preference or utility, it will no longer be clear what we mean by welfare, and hence we make welfare-enhancing policy ill-defined. Nevertheless, preference is now in a troubling moment in the development of economics. Even though its existence has been questioned, the development of neuroeconomics may further deepen this turbulent situation.