“I have a student called Suby Roy…”: Reflections on Frank Hahn (1925-2013), my master in economic theory


1. “What was relatively weak at LSE was general economic theory. We were good at deriving the Best Linear Unbiased Estimator but left unsatisfied with our grasp of the theory of value that constituted the roots of our discipline. I managed a First and was admitted to Cambridge as a Research Student in 1976, where fortune had Frank Hahn choose me as a student. That at the outset was protection from the communist cabal that ran “development economics” with whom almost all the Indians ended up. I was wholly impecunious in my first year as a Research Student, and had to, for example, proof-read Arrow and Hahn’s General Competitive Analysis for its second edition to receive 50 pounds sterling from Hahn which kept me going for a short time. My exposure to Hahn’s subtle, refined and depthless thought as an economist of the first rank led to fascination and wonderment, and I read and re-read his “On the notion of equilibrium in economics”, “On the foundations of monetary theory”, “Keynesian economics and general equilibrium theory” and other clear-headed attempts to integrate the theory of value with the theory of money — a project Wicksell and Marshall had (perhaps wisely) not attempted and Keynes, Hicks and Patinkin had failed at.



Hahn insisted a central question was to ask how money, which is intrinsically worthless, can have any value, why anyone should want to hold it. The practical relevance of this question is manifest. India today in 2007 has an inconvertible currency, vast and growing public debt financed by money-creation, and more than two dozen fiscally irresponsible State governments without money-creating powers. While pondering, over the last decade, whether India’s governance could be made more responsible if States were given money-creating powers, I have constantly had Hahn’s seemingly abstruse question from decades ago in mind, as to why anyone will want to hold State currencies in India, as to whether the equilibrium price of those monies would be positive. (Lerner in fact gave an answer in 1945 when he suggested that any money would have value if its issuer agreed to collect liabilities in it — as a State collects taxes – and that may be the simplest road that bridges the real/monetary divide.)



Though we were never personal friends and I did not ingratiate myself with Hahn as did many others, my respect for him only grew when I saw how he had protected my inchoate classical liberal arguments for India from the most vicious attacks that they were open to from the communists. My doctoral thesis, initially titled “A monetary theory for India”, had to be altered due to paucity of monetary data at the time, as well as the fact India’s problems of political economy and allocation of real resources were more pressing, and so the thesis became “On liberty and economic growth: preface to a philosophy for India”. When no internal examiner could be found, the University of Cambridge, at Hahn’s insistence, showed its greatness by appointing two externals: C. J. Bliss at Oxford and T. W. Hutchison at Birmingham, former students of Hahn and Joan Robinson respectively. My thesis received the most rigorous and fairest imaginable evaluation from them…”



2. “Frank Hahn believed in throwing students in at the deep end — or so it seemed to me when, within weeks of my arrival at Cambridge as a 21 year old Research Student, he insisted I present my initial ideas on the foundations of monetary theory at his weekly seminar.




I was petrified but somehow managed to give a half-decent lecture before a standing-room only audience in what used to be called the “Keynes Room” in the Cambridge Economics Department. (It helped that a few months earlier, as a final year undergraduate at the LSE, I had been required to give a lecture at ACL Day’s Seminar on international monetary economics. It is a practice I came to follow with my students in due course, as there may be no substitute in learning how to think while standing up.) I shall try to publish exactly what I said at my Hahn-seminar when I find the document; broadly, it had to do with the crucial problem Hahn had identified a dozen years earlier in Patinkin’s work by asking what was required for the price of money to be positive in a general equilibrium, i.e. why do people everywhere hold and use money when it is intrinsically worthless. Patinkin’s utility function had real money balances appearing along with other goods; Hahn’s “On Some Problems of Proving the Existence of an Equilibrium in a Monetary Economy” in Theory of Interest Rates (1965), was the decisive criticism of this, where he showed that Patinkin’s formulation could not ensure a non-zero price for money in equilibrium. Hence Patinkin’s was a model in which money might not be held and therefore failed a vital requirement of a monetary economy. The announcement of my seminar was scribbled by a young Cambridge lecturer named Oliver Hart, later a distinguished member of MIT and Harvard University.”



3.   Then there was Sraffa…I saw him many a time, in the Marshall Library… He would smile very broadly at me and without saying anything  indicate with his hand to invite me to his office.. I fled in some fear… It was very stupid of me of course… Joan Robinson cornered me once and took me into the office she shared with EAG… She came at me for an hour or so wishing to supervise me, I kept declining politely… saying I was with Frank Hahn and wished to work on money… “What does Frankie know about India?” she said… I said I did not know but he did know about monetary theory and that was what I needed for India;  I also said I did not think much about the Indian Marxists she had supervised… and mentioned a prominent name… she said about him, “Yes most of what he does can go straight into the dustbin”…



4.   “I had been attracted to Cambridge partly by its old reputation for philosophy, especially that of Wittgenstein. But I met no worthwhile philosophers there until a few months before I was to leave for the United States in 1980, when I chanced upon the work of Renford Bambrough. Hahn had challenged me with the question, “how are you so sure your value judgements promoting liberty blah-blah are better than those of Chenery and the development economists?” It was a question that led inevitably to ethics and its epistemology — when I chanced upon Bambrough’s work, and that of his philosophical master, John Wisdom, the immense expanse of metaphysics (or ontology) opened up as well. “Then felt I like some watcher of the skies, When a new planet swims into his ken; Or like stout Cortez when with eagle eyes, He star’d at the Pacific…””



5. “I went to Virginia because James M. Buchanan was there, and he, along with FA Hayek, were whom Hahn decided to write on my behalf. Hayek said he was too old to accept me but wrote me kind and generous letters praising and hence encouraging my inchoate liberal thoughts and arguments. Buchanan was welcoming and I learnt much from him and his colleagues about the realities of public finance and democratic politics, which I quickly applied in my work on India…” Hahn told me he did not know Buchanan but he did know Hayek well and that his wife Dorothy had been an original member of the Mont Pelerin Society in 1947 or 1948. Hence I am amused reading a prominent NYU “American Austrian” say about Frank’s passing “I do think economics would have been better off if the Arrow-Debreu-Hahn approach had not been taken so seriously by the profession. I think it turned out to be an intellectual straight-jacket that prevented the discussion of valuable outside-the-box ideas”, and am tempted to paraphrase the closing lines of Tractatus — “Whereof one cannot speak, thereof one must be silent/About what one can not speak, one must remain silent” — to read “Of that of which we are ignorant, we should at least try not to gas about…” Hahn and Hayek were friends, from when Hayek taught at the London School of Economics in Robbins’ seminar, and Hahn was Robbins’ doctoral student.



6. “The Hawaii project manuscript contained inter alia a memorandum by Milton Friedman done at the request of the Government of India in November 1955, which had been suppressed for 34 years until I published it in May 1989. Milton and Rose Friedman refer to this in their memoirs Two Lucky People (Chicago 1998). Peter Bauer had told me of the existence of Friedman’s document during my doctoral work at Cambridge under Frank Hahn in the late 1970s, as did N. Georgescu-Roegen in America. Those were years in which Brezhnev still ruled in the Kremlin, Gorbachev was yet to emerge, Indira Gandhi and her pro-Moscow advisers were ensconced in New Delhi, and not even the CIA had imagined the Berlin Wall would fall and the Cold War would be over within a decade. It was academic suicide at the time to argue in favour of classical liberal economics even in the West. As a 22-year-old Visiting Assistant Professor at the Delhi School of Economics in 1977, I was greeted with uproarious laughter of senior professors when I spoke of a possible free market in foreign exchange. Cambridge was a place where Indian economists went to study the exploitation of peasants in Indian agriculture before returning to their friends in the well-known bastions of such matters in Delhi and Calcutta. It was not a place where Indian (let alone Bengali) doctoral students in economics mentioned the unmentionable names of Hayek or Friedman or Buchanan, and insisted upon giving their works a hearing. My original doctoral topic in 1976 “A monetary theory for India” had to be altered not only due to paucity of monetary data at the time but because the problems of India’s political economy and allocation of resources in the real economy were far more pressing. The thesis that emerged in 1982 “On liberty and economic growth: preface to a philosophy for India” was a full frontal assault from the point of view of microeconomic theory on the “development planning” to which everyone routinely declared their fidelity, from New Delhi’s bureaucrats and Oxford’s “development” school to McNamara’s World Bank with its Indian staffers. Frank Hahn protected my inchoate liberal arguments for India; and when no internal examiner could be found, Cambridge showed its greatness by appointing two externals, Bliss at Oxford and Hutchison at Birmingham, both Cambridge men.”



7. “I have a student called Suby Roy…”  Frank sends me to America in 1980 to work with Jim Buchanan… One letter from him was all it took…






And then five years later in 1985 he calls me “probably the outstanding young Hayekian”, says I had brought “a good knowledge of economics and of philosophy to bear on the literature on economic planning”, had “a good knowledge of economic theory” and that my “critique of Development Economics was powerful not only on methodological but also on economic theory grounds” — all that to me has been a special source of delight.




We did not meet often after I left Cambridge but he wrote very kindly always, and finally said, hearing of my travails and troubles and adventures, “well you are having an interesting life…”…



In America, I once met Robert M Solow in a hotel elevator as we were on a  panel at a conference together; I  introduced myself as Hahn’s student… “Aren’t you lucky?” said Solow with a smile…and he was right… I was lucky…



I said of Milton Friedman that he had been “the greatest economist after John Maynard Keynes”;  Milton’s critic, Frank Hahn, may have been the greatest economic theorist of modern times.




                                                                      Frank Hahn (1925-2013)


“Oh, Renford? He’s a genius!”: A post-War Cambridge story

“Oh, Renford? He’s a genius!” That is what the late Dharma Kumar (1928-2001) said to me in the summer of 1998 at her Delhi home in what would be our last meeting.

I was taken aback.  She and I had met after a long decade.  Discussing what I had been up to, I had mentioned my application of the work of Renford Bambrough to economic theory in my 1989 book Philosophy of Economics.

“Oh, Renford? He’s a genius!” —  Dharma repeated blandly, seeming surprised that I did not get it.

“Oh, Renford? He’s a genius!” — she said a third time more slowly, and then, seeing my uncomprehending stare,  explained to me that that was the common saying at Cambridge about the young Renford Bambrough back in the post-War years when she had herself arrived there as an undergraduate.

Now, finally, I got it.  “Oh, Renford? He’s a genius!”

In “Conflict and the Scope of Reason”, Renford Bambrough recounted that he had, around 1948, crossed the great Bertrand Russell himself at a meeting of the Labour Club.  Russell had made a proposal (which he apparently denied later ever having made) of preventive atomic war against the USSR.  Sooner or later there would be conflict between the USSR and the West, the argument went, on balance it would be worse  to live under pax Sovietica than pax Americana; therefore, Russell had argued, the West’s existing power should be used to ensure the Soviets never acquired the same.   At question-time, young Renford, aged 22, asked Russell why, from a purely philosophical point of view, it mattered  “if the human race did destroy itself rather than die of natural causes later”.  There was laughter among the audience, and then Russell said he had enormously liked the question, and wished he could “achieve the degree of detachment here displayed by one so young.  But I confess that I, for my part, have never been able to overcome my feelings of concern for the welfare of the species of which I am a member”.  Russell had misunderstood the question or deftly avoided it, but even so he had noticed in his young interlocutor the calm detachment that would mark all his later thought.

John Renford Bambrough was born on April 29 1926 and died on January 17th 1999.  I have written a little about him here and shall write more fully about him anon.

Subroto Roy

Alfred Marshall (1842-1924)

Alfred Marshall (1842-1924), founder of modern economics, master of Maynard Keynes, concluding his 1885 Inaugural Lecture: “It will be my most cherished ambition, my highest endeavour, to do what with my poor ability and my limited strength I may, to increase the numbers of those, whom Cambridge, the great mother of strong men, sends out into the world with cool heads but warm hearts, willing to give some at least of their best powers to grappling with the social suffering around them; resolved not to rest content till they have done what in them lies to discover how far it is possible to open up to all the material means of a refined and noble life”.