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Irving Fisher—Mathematical investigations

Cunynghame:* “But curves play in the study of pol. econ.much the same part as the moods and figures play in logic. Theydo not perhaps assist in original thought, but they afford asystem by means of which error can be promptly and certainlydetected and demonstrated. And as in logic so in graphic pol.econ. the chief difficulty is not to solve the problem, but to state itin geometrical language.”

§ 8 -

Contrast with the preceding the following statements from a fewwho can see nothing good in mathematical method :

A writer in the “ Saturday Review ” (Nov. 11, 1871), quoted byProf. Edgeworthf says of Jevons : “The equations, * * * assum-ing them to be legitimate, seem to us to be simply useless so long asthe functions are obviously indeterminable.” [Mathematics studiesrelations as well as calculations. Numerical indeterminability iscommon even in mathematical physics.]

CairnesiX “Having weighed Prof. Jevons ’s argument to the bestof my ability, and so far as this is possible for one unversed inmathematics, I still adhere to my original view. So far as I can see,economic truths are not discoverable through the instrumentality ofmathematics. If this view be unsound, there is at hand an easymeans of refutation—the production of an economic truth, notbefore known, which has been thus arrived at ; but I am not awarethat up to the present any such evidence has been furnished of theefficiency of the mathematical method. In taking this ground, Ihave no desire to deny that it may be possible to employ geometricaldiagrams or mathematical formulce for the purpose of exhibitingeconomic doctrines reached by other paths, and it may be that thereare minds for which this mode of presenting the subject has advan-tages. What I venture to deny is the doctrine which Prof. Jevons and others have advanced—that economic knowledge can be ex-tended by such means; that mathematics can be applied to thedevelopment of economic truth, as it has been applied to the devel-opment of mechanical and physical truth ; and, unless it can be

* Geometrical methods of treating exchange value, monopoly and rent. H.Cunynghame. Econ. Jour., March, ’92, p. 36.

f Math.-Psychics, p. 119.

\ The Character and Logical Method of pol. econ. New York , 1875. PrefaceSee also, p. 122; also: Some leading principles of pol. econ. newly expounded.Preface.