Fads are as common in mathematics as in any other human activity, and it is always difficult to separate the enduring from the ephemeral in the achievements of one s own time. An unfortunate effect of the predominance of fads is that if a student doesn t learn about such worthwhile topics as the wave equation, Gauss s hypergeometric function, the gamma function, and the basic problems of the calculus of variations among others as an undergraduate, then he/she is unlikely to do so later.

The natural place for an informal acquaintance with such ideas is a leisurely introductory...