PREFACE
TO THIS REPRINT.
The following booklet is a photo-engraved reprint of my doctor’s thesis,long since-out of print, and first published in the Transactions of theConnecticut Academy of Arts and Sciences, in 1892.
Twenty-five years later, in the midst of the World War, much to mysurprise and pleasure, a French translation was made by Jacques Moret.*
Occasionally mathematical economists have suggested that the originalAmerican edition should be reprinted, one of them maintaining that “thebook has become recognized as an economic classic and should be moreavailable.” So here it is, a third of a century after its first publication.
I cannot honestly recommend that it be read entire by anybody. But inmy own classes I have, for many years, found use for pages 11-54 andpages 64-79. The book was written when I was more interested in mathe-matics than in economics. The vector analysis notation on page 81 was atribute to J. Willard Gibbs , whose student I then was and who took alively interest in the work.
The “Bibliography on Mathematico-Economic Writings” at the end wassuperseded years ago by my “Bibliography of Mathematical Economics”on pages 173-209 of Nathaniel T. Bacon’s English translation of Cournot (“Researches into the Mathematical Principles of the Theory of Wealth”)in the Economic Classics Series, edited by Professor W. J. Ashley andpublished by Macmillan in 1897.
The hydrostatic mechanism pictured on page 38 has been actually con-structed—twice in fact. In 1893, the year after the thesis was published,my colleague, Professor Henry W. Farnam, generously defrayed the ex-pense of constructing a model. This was used in my classes for manyyears. Eventually it wore out and was recently (1925) replaced by a sec-ond model somewhat improved and simplified. Photographs of both thesemodels are reproduced herewith.
As I look back on this youthful production I take some satisfaction infinding that my treatment of so-called “marginal utility” and criticism ofthe then current notions of a “calculus of pleasure and pain” are in tunewith modem psychology and that this fact has been favorably commentedon by Professor Wesley C. Mitchell.