The extraordinary mind of Frank Ramsey

Unless you have studied philosophy, maths or economics, it is unlikely you have heard of Frank Ramsey. And if you have, it is probably as a minor character in stories about his celebrated Cambridge philosophical contemporaries Bertrand Russell and Ludwig Wittgenstein.

That’s a shame. Even as a teenager Ramsey displayed a genius to rival these figures. He was Wittgenstein’s favourite intellectual sparring partner. GE Moore revered him. AJ Ayer, meanwhile, once said it was a great pity that Cambridge philosophers spent the 1930s “chewing over Wittgenstein when they ought to have been chewing over Ramsey.” And he was revolutionary not only in philosophy and maths, but also economics: Keynes found Ramsey’s criticisms devastating and agonised over how to answer them. This is all the more remarkable given that Ramsey died at the age of 26 from a mystery liver ailment. 

Today there are professorships bearing his name not only at Cambridge but also at Harvard; there is even a Frank Ramsey medal. Even so, he should occupy a much more prominent place in the story of modern philosophy. Despite the posthumous publication in 2012 of a memoir written by his sister, Margaret Paul, there has never been a comprehensive biography—until now. In her important new work, Cheryl Misak, of the University of Toronto, finally gives Ramsey the consideration he deserves. Misak has access to previously unaired interviews with family members shared with her by documentary-maker Laurie Kahn, who had planned to write a thesis on Ramsey while a student. Her project is both to truly render the life of this little-known thinker and to put his work in its proper place. 

As a child, Ramsey was something of a prodigy, even in the context of a gifted family—his brother Michael went on to become Archbishop of Canterbury. Arriving at Cambridge in 1920, he was described by Keynes as “far and away the most brilliant undergraduate who has appeared for many years in the border country between philosophy and mathematics.” Moore was so intimidated by his intellectual abilities that he was afraid to lecture to him. By his early twenties, Ramsey was a full fellow at King’s, and would holiday with the Bloomsbury set. Yet he did not have the typical temperament of an intellectual prima donna: he was a “very stable genius.” Compared to some of his colleagues and friends, he was quieter and more grounded. But there are now no fewer than 19 techniques, models, theorems and phenomena bearing his name, and across a wide range of academic disciplines. 

One of Misak’s contentions is that as a man and a thinker Ramsey faced the world with an unflinching focus on how things really are, rather than how he would have liked them to be. He viewed religion as a fantasy, which must have led to some uncomfortable moments at family dinners. In three successive years, he wrote three profound papers on economics, in three very different areas, each with implications that lesser minds would be grappling with for decades. One, drawing on his mastery of probability, created a new framework for analysing expectations about the future (crucial in macroeconomics and finance); another introduced an original and practical theory governing rates of taxation and what monopolies should be allowed to charge; the last interrogated the optimal amount that a nation should save for the future. Keynes called this final paper “one of the most remarkable contributions to mathematical economics ever made, both in intrinsic importance and difficulty of its subject.”

In maths, he made leaps in “combinatorics,” studying the properties of different systems and under what conditions order emerges. A simple piece of combinatorics is to imagine a party and ask: what is the smallest number of total guests such that there are either three mutual strangers or three mutual acquaintances (assuming everyone knows the host)? The answer is six, which is what we now know as a “Ramsey number.” To guarantee four mutual friends or strangers we have to invite 18 people, and so on. The hunt for Ramsey numbers is ongoing.

It was, however, in philosophy that Ramsey made his greatest mark. Having cut his teeth scrutinising the formal logic of Russell’s Principia Mathematica, he later made breakthroughs in epistemology, the study of knowledge, contributing arguably the first “reliabilist” theory, which links knowledge to that which enables us to act reliably in future. The practical-minded among us would find little about that to quibble with. Our inferences and beliefs are justified at least in part by the success of having them. Versions of this idea still have prominent adherents today.

The common-sense approach is also stark in Ramsey’s arguments on induction—the drawing of likely conclusions from a set of premises: for example, the sun rises tomorrow because it has risen today and yesterday—and how we can trust it as a process of reasoning. The question has animated philosophers for centuries. “We are all convinced by inductive arguments,” he said simply, “and our conviction is reasonable because the world is so constituted that inductive arguments lead on the whole to true opinions. We are not, therefore, able to help trusting induction, nor if we could help it do we see any reason why we should.” 

He published celebrated papers including “The Foundations of Mathematics,” “Fact and Propositions” and “On Truth,” and was in the process of expanding the last of these into a book when he died. There is “Ramsey pricing,” a “Ramsey-Cass-Koopmans model,” even “Ramsey sentences.” Donald Davidson, himself a celebrated philosopher, coined the “Ramsey effect”: when you find out that your new idea was in fact already discovered by Frank Ramsey, and that he put it better than you did. 

But any account of Ramsey’s life must ultimately turn to his work with Wittgenstein. Wittgenstein’s first book the Tractatus Logico-Philosophicus (1921) was a masterpiece in the philosophy of language, designed to delineate the relationship between words and the world and arguing that propositions have a sort of “picture” relationship with reality, a sentence being meaningful because of the way in which it refers to the state of affairs “out there.” 

Wittgenstein invited Ramsey to spend a fortnight with him going through a draft, and corrected his manuscript in light of his criticisms. The Austrian was notoriously volatile and accused Russell and Moore of being utterly unable to understand him. Yet Ramsey was commissioned to translate the Tractatus from German to English, with Wittgenstein’s approval. There is some debate but it seems likely Wittgenstein admired the finished translation.

Wittgenstein immodestly claimed to have solved all the problems of philosophy with this work. But Ramsey was not convinced. He would come to believe that it had a gap, one that should be filled with a more pragmatic view of the way we use words. It was partly in response to Ramsey’s criticisms that Wittgenstein later dramatically changed approach, producing what would become his Philosophical Investigations, published posthumously in 1953, with its radically different theory (or anti-theory) that the meaning of a word is simply its use in the language. In the book’s preface, Ramsey is credited as an influence. The two often disagreed, including in their philosophies of language. Indeed Wittgenstein did not believe Ramsey to have a true philosophical outlook, viewing his practical mindset as more that of a scientist. For Ramsey’s part, he thought that Russell, Moore and the earlier Wittgenstein all “turned their backs on actual human and practices and inquiry,” and grew increasingly determined to avoid that mistake. 

Does Misak’s book do Ramsey justice? Certainly it is an impressive work. She has a devotion to the archive and her book is thoroughly researched and well put together. But it is heavy going in places—one footnote discusses “an algebraic construction that treats universal generalisations as conjunctive propositions in a modal context.” This is particularly so in the information boxes dotted throughout the book: when Ramsey engages with a subject not in Misak’s wheelhouse, she enlists another expert to explain it over a page or two, while advising that you can skip them if you prefer. Such are the perils of trying to have the final word on every aspect of a polymath. 

Misak’s overriding aim is to show Ramsey as a thinker who bridged the gap between the pragmatic tradition and the abstruse world of analytic philosophers. He introduced human good sense where it was needed, nudging his contemporaries that way too. For her, this is his singular contribution. 

This is reasonable enough. Good sense does run like a thread through Ramsey’s work and we are provided with plenty of examples: his work on causation, counterfactuals and generalisations is fitted into the theme. “Philosophy must be of some use,” Ramsey said. And indeed his work in economics showed he would sometimes descend from rarefied philosophical heights to address practical problems. 

But I suspect the lay reader will be struck by something rather different. It’s unlikely he or she will judge the philosophy down-to-earth when they have just digested an argument, however important, about the validity of propositions in formal systems. Even though there was a pragmatism not present in the work of others, it is not pragmatism as we usually think of it. Indeed, it feels emphatically removed from everyday reality. 

No, what stands out for me is the character of the man. Despite his intellectual milieu (and some biographical curios), Ramsey truly was a humble man. So many thinkers we learn about were dominating personalities, attracting widespread attention and earning infamy. Perhaps this is another reason why Ramsey was not as famous as some of his contemporaries. Russell was a controversial public intellectual with a rackety private life while Wittgenstein was eccentric in the extreme, his forceful character inspiring intense devotion in his disciples.

Ramsey was different. He was essentially an ordinary man with an extraordinary mind. He played tennis. He went for walks. He would go out of his way to do favours for other people. His relationship with his family was a little unorthodox, but ultimately loving. And as an adult, he was capable of happiness—in contrast to the melodramatic moodiness of the others he worked with. As he once closed a lecture: “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.” When he died there was grief for someone who, despite his “excess of powers,” struck those who met him as considerate and humble. 

What might have Ramsey achieved if he had lived? Certainly, he would have finished the book on truth and belief he was working on. More speculatively some ask whether in pure mathematics he would have beaten Kurt Gödel to the great prize of proving the incompleteness of arithmetic. Who can say? We should feel lucky that we have the work we do, and that Misak has done such a good job of drawing our attention to one of the most important and intriguing figures in 20th-century philosophy.

Frank Ramsey: A Sheer Excess of Powers by Cheryl Misak (OUP, £25)