Avi,
     Thanks for the info on Gordon's view.  However, even if he is right about Marshall's motivation, this does not make much sense to me.  CS and PS are areas in P-Q space, and it does not matter
a whit which one is on which axis for making such a measurement.  I would think that someone as mathematically sophisticated as Marshall would understand this.
Barkley
________________________________________
From: Societies for the History of Economics [[log in to unmask]] on behalf of Avi J. Cohen [[log in to unmask]]
Sent: Saturday, February 05, 2011 9:55 AM
To: [log in to unmask]
Subject: [SHOE] why Marshall transposed the axes

Barkley,

Forgive my delay, but I only receive the SHOE list in digest form, once a day.

The main reason is that Marshall privileged the geometric analysis and measurement of consumer and producer surplus, in order to asses welfare effects.

Here are key summary quotes from Gordon:

Main reason "why Marshall adopted the price-function form was that he wished to interpret the price consumers are willing to pay as a measurement of utility and the price producers are willing to accept as a commensurable measurement of real (disutility) cost of production. In order to understand Marshall's diagrammatic practice we must pay attention to his normative welfare economics" (32)


"Why did Marshall transpose Cournot's axes? The answer, in my view, lies in Marshall's early, and continuing, interest in consumer and producer surplus, that is, in what we today call 'normative welfare economics,' as one of the main objects of economic analysis. There is no substantive difference, as such, in labeling coordinate axes one way or the other, but Marshall, in my opinion, put quantity on the abcissa and price on the ordinate because in doing the analysis of 'maximum satisfaction' this would be in accord with the mathematical convention of using the abcissa for the independent, and the ordinate for the dependent, variables."  (35)

Conclusion

"A demand (supply) curve can be read two ways: as a statement of the quantities consumers (producers) will buy (sell) at different prices, or as a statement of the prices consumers (producers) are willing to pay (accept) for different quantities. According to the first reading, mathematical convention requires that quantity be treated as the dependent variable and price as the independent variable, and diagrammed accordingly, but the second reading requires the opposite treatment. In this paper I have shown that Marshall interpreted demand (supply) functions in the second of these two ways from his earliest work in economic theory, and have argued that his treatment was, from the beginning and throughout his subsequent work, motivated by his desire to use price as a money measurement of benefits and costs in order to construct a theory of surplus serviceable for welfare economics. Thus, Marshall's diagrammatic practice was neither idiosyncratic nor mistaken, when viewed in terms of what he regarded to be the main purpose of economic theory."  (43-4)


The article is very rich, and I encourage you to look at it. I have a pdf of the article, which I am happy to send to anyone who emails me (SHOE does not accept attachments). The digital version of EEJ does not go back to 1982.

Best,

Avi


From: "Rosser, John Barkley - rosserjb" <[log in to unmask]<mailto:[log in to unmask]>>
Date: February 4, 2011 9:32:17 AM EST
Subject: Re: why Marshall transposed the axes

Avi,
     For those without quick access to this article, what is Gordon's answer roughly, please?
Barkley
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From: Societies for the History of Economics [[log in to unmask]] on behalf of Avi J. Cohen [[log in to unmask]]
Sent: Friday, February 04, 2011 8:07 AM
To: [log in to unmask]<mailto:[log in to unmask]>
Subject: [SHOE] why Marshall transposed the axes

Steve,

See Scott Gordon, "Why Marshall Transposed the Axes"  Eastern Economic Journal 8 (1) Jan 1982: 31-45

Best,

Avi