The great Cambridge mathematician economist and philosopher 1903

The great Cambridge mathematician, economist and philosopher 1903 -1929

Academic’s fairytale Laurie Kahn Ramsey Collection at the Fisher Rare Book Library, University of Toronto

‘Certainly, that young man was a Subtitle from Joseph Schumpeter true product of Cambridge at its best —nobody can have any doubt about it who ever met him, which the present writer did but once. In discussion he impressed one curiously like an overgrown two-year -old who misbehaves on the racecourse from sheer excess of powers. ’

Mathematics Undergraduate Cambridge 1920 -1923

G. E. Moore ‘In the early twenties, F. P. Ramsey attended at least one course of my lectures. I had soon come to feel of him, as of Wittgenstein, that he was very much cleverer than I was, and consequently I felt distinctly nervous in lecturing before him: I was afraid that he would see some gross absurdity in things which I said, of which I was quite unconscious. ’

‘The Douglas Proposals’ 1922 Commissioned by Keynes and Ogden.

‘Mr Keynes on Probability’ 1922 Clive Bell: ‘Ramsey made a rent’ in Keynes’s theory of probability ‘which caused the stitches to run. ’

Undergraduate thesis: ‘The Foundations of Mathematics’ Tried to repair a problem in Russell and Whitehead’s Principia Mathematica and improve on theory of types. It didn’t win the Smith’s Prize.

Harold Jeffreys ‘It sort of leaked round to me that they’d consulted somebody who said that it wasn’t very good – said that his paper wasn’t very good! Then Bertrand Russell, afterwards was consulted, said that his work was first rate, which made various people wonder who the hell was the expert that they had consulted!’

It had a major impact on the Vienna Circle The Circle talked about the paper for two weeks in January 1927 and then intermittently through to 1929.

Translated Wittgenstin’s Tractatus-Logico. Philosophicus

Don in Mathematics at 21, at King’s Richard Braithwaite: ‘Then of course, Keynes snapped him up, before he got in at Trinity. I’m sorry, do you know the expression, pounced. Keynes got King's to pounce. 'I hadn't realised Keynes's ability to get the college to agree to pounce him. '

He became a Superstar in 4 disciplines, at least. Pure Mathematics Economics Subjective Probability/Expected Utility Theory Philosophy

Pure Mathematics Ramsey Theory: the conditions under which order must occur

Published two papers in Keynes’s Economic Journal Economic s ‘A Mathematical Theory of Saving’ ‘A Contribution to the Theory of Taxation’

In 2015, when the Journal celebrated its 125 th anniversary with a special edition, both of Ramsey’s papers were included. The editors explained the unusual step of including two papers by one author: the papers initiated ‘entirely new fields’

Subjective Probability/Expected Utility Theory 1926, a few years before de Finetti, Ramsey figured out how to measure partial belief; put forward a theory of probability as subjective degree of belief; and showed that rationality could be understood as expected utility.

These results play a prominent role in contemporary economics and Bayesian statistics, as well as much of psychology, artificial intelligence, etc.

Ramsey would not have liked what became of his idea in economics No real person can have a set of beliefs that are perfectly coherent in terms of the probability calculus. He was talking about a highly idealised system ‘to which those of actual people, especially the speaker, in part approximate’.

He was a socialist, like his friends Maurice Dobb and Piero Sraffa.

Philosophy Many things are named for him: Ramsey Sentences, the Ramsey Test for Conditionals, and on.

My favourite is from Donald Davidson The Ramsey Effect: discovering that your exciting and apparently original philosophical discovery has been already presented, and presented more elegantly, by Frank Ramsey when he was 26 years old.

He was one of a very few people who could counter Wittgenstein

He had a profound influence on Wittgenstein, persuading him to drop the quest for certainty and purity, and turn to ordinary language and human practices. Ramsey was in search of a ‘realistic’ philosophy and was leaning in the direction of American pragmatism when he died.

Ramsey 1929 ‘We cannot really picture the world as disconnected selves; the selves we know are in the world. What we can’t do and it’s no good trying. Philosophy comes from not understanding the logic of our language; but the logic of our language is not what Wittgenstein thought. The pictures we make to ourselves are not pictures of facts. ’

All this, and he died at the age of 26 From Leptospirosis, or Weil’s Disease, caused by bacteria carried by the urine of animals, and often found in the River Cam.

Lytton Strachey to Dadie Rylands ‘The loss to your generation is agonizing to think of – and the world will never know what has happened – what a light has gone out. I always thought there was something of Newton about him – the ease and majesty of the thought – the gentleness of the temperament. ’

How can any one person, who is not Ramsey himself, possibly write an intellectual biography of Ramsey?

Guest Boxes Partha Dasgupta on Ramsey’s economics Huw Price, Simon Blackburn, Michael Potter on topics in philosophy and the foundations of mathematics

• Ronald Graham on Ramsey Theory

Ramsey also had an excellent and interesting personal life Frances Partridge (Marshall)

Lettice Cautley Ramsey Renowned portrait photographer and adventurer

Came up to Cambridge a year after the Great War. Part of the English migration to Vienna for psychoanalysis in the early 1920 s. Part of Bloomsbury and the Apostles

Kingsley Martin (future editor of the New Statesman), Irene Martin (Barclay) (Britain’s first female chartered surveyor and an advocate for improved housing conditions for the poor) and Paul Redmayne (of the Cadbury family).

Family

Elizabeth Denby Influential housing reformer for the poor.

Xu Zhimo, Pat Blackett, Lionel Penrose

Bloomsbury

The last word should be Ramsey’s Untitled Paper read to the Apostles 1925

It was a response to Wittgenstein, who had scorned the Apostles as having ‘nothing to discuss’ and who thought that everything outside of the primary language of logic and direct experience was unsayable or ineffable.

It was also about the meaning of life Wittgenstein said you can’t talk about the meaning of life. But it is depressing.

Russell said that you can talk about it, and it is depressing ‘All the labours of the ages, all the devotion, all the inspiration, all the noonday brightness of human genius, are destined to extinction in the vast death of the solar system. The whole temple of Man's achievement must inevitably be buried beneath the débris of a universe in ruins. ’

Ramsey ‘Where I seem to differ from some of my friends is in attaching little importance to physical size. I don’t feel the least humble before the vastness of the heavens. The stars may be large, but they cannot think or love; and these are qualities which impress me far more than size does. I take no credit for weighing nearly seventeen stone. ’

‘My picture of the world is drawn in perspective, and not like a model to scale. The foreground is occupied by human beings and the stars are all as small as threepenny bits. I apply my perspective not merely to space but also to time. In time the world will cool and everything will die; but that is a long time off still, and its present value at compound discount is almost nothing. ’

‘Nor is the present less valuable because the future will be blank. Humanity, which fills the foreground of my picture, I find interesting and on the whole admirable. I find, just now at least, the world a pleasant and exciting place. You may find it depressing; I am sorry for you, and you despise me. But I have reason and you have none. I pity you with reason, because it is pleasanter to be thrilled than to be depressed, and not merely pleasanter but better for all one’s activities. ’

Those philosophers who focus on the vastness and the unknowability of the world are on the wrong track about the meaning of life. His Argument What we are interested in is the world of human beings and making things better for them. We can discuss or assess our feelings about the meaning of life (and ethics) in these terms—in terms of their impacts on human life and behavior.

One reason Ramsey was so pleased with his life is that he was solving problems—in highly theoretical matters, but also about how much a nation should save for the future; whether we should discount future generations; how we should think about progressive politics and ways of life that may not be good right now for the working class, etc.

That work was cut very short. We can only guess what he might have done.