Ramsey was more than a polymath, he excelled in every field that he pursued. In fact, he made groundbreaking advancements in pure math, mathematical logic, foundations of math, probability theory, decision theory, philosophy, and economics. He also contributed to applied math, ethics, and psychology. Misak’s biography details his academic contributions, his personal relationships with Russell, Moore, Wittgenstein, Keynes, Sraffa, and other Cambridge luminaries, as well as his open marriage to Lettice and his eccentric friendships with the rest of the Bloomsbury set.
Ramsey was universally respected by his academic peers. G.E. Moore recalls teaching him as an undergrad at Trinity College, “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.” This from the man who Bertrand Russell considered the greatest philosopher at Cambridge. Ramsey’s classmate (and later a colleague as a Fellow at King’s College) R.B. Braithwaite remembered, “By his second year he was accepted as the arbiter of good reasoning on every abstract subject: for eight years, if an abstruse point arose in philosophy, psychology, logic, economics, the question was ‘What does Frank Ramsey think of it?’ At conferences of philosophers, at the High Table or at undergraduate parties, his opinion on the value or relevance of an argument carried a peculiar and decisive authority.”
Ramsey began his professional career as a Fellow at King’s College by taking on Russell, the recognized preeminent mind in formal logic at Cambridge. “Ramsey found ‘important defects’ in Principia. Most important was the ‘failure’ of Russell’s Theory of Types to overcome the difficulties generated by the paradoxes…. Ramsey began ‘The Foundation of Mathematics’, by agreeing with the logicians that mathematics is a part of logic…. Against the formalist view of Hilbert, he said that mathematics does not consist of ‘meaningless formulae to be manipulated according to certain arbitrary rules’…. Against the intuitionists Brouwer and Weyl, he asserted that in restricting themselves to what can in principle be constructed by human mathematicians, they give up ‘many of the most fruitful methods of modern analysis, for no reason, as it seems to me, except that the methods fail to conform to their private prejudices’…. He thought the first part of Russell’s Theory of Types was fine. It asserted that to apply a predicate to the wrong type of subject does not produce a falsehood—rather, it produces something that is literally nonsense.” However, Ramsey found an error in “the introduction of the axiom of reducibility, which asserts that for any predicate of a higher order there is a predicate of a lower order which applies to the same set of subjects. But, as Ramsey noted (following something Wittgenstein said in the Tractatus), this is a genuine proposition, set out in words, ‘whose truth or falsity is a matter of brute fact, not of logic’. This so-called axiom ‘is certainly not self-evident, and there is no reason whatever to suppose it true’…. Russell had introduced an axiom that was not a tautology, in order to save the theory from contradiction. But in doing so, he had abandoned the project of building a self-evidently true theory…. Paradoxes belonging to the second category ‘contain some reference to thought, language, or symbolism’, hence are ‘due not to faulty logic or mathematics, but to faulty ideas concerning thought and language’…. For contradictions of a purely mathematical nature, such as paradoxes that arise by considering classes that are members of themselves, Ramsey held that Russell’s Theory of Types would suffice. But Russell’s theory doesn’t work for the second category of paradoxes, which involve ‘meaning’ or ‘ambiguities of language’.” In an important move, “Ramsey argued that mathematical truths, like logical truths, are tautologies in Wittgenstein’s sense.”
Ramsey would next defend his philosophic worldview that included personal feelings and ethics as in some ways objective. Again, his jumping off point would be Russell, while also taking on Ludwig Wittgenstein, as well. “Ramsey returned, as promised, to Russell’s ‘What I believe’. He says that if he were to write such a Weltanschauung (a world-view) he would call it ‘What I Feel’…. Wittgenstein’s position in the Tractatus was that the world of the happy person is simply a different world to that of the sad person, with no discussion possible as to the merits of either world.” Ramsey argued, “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 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; you would only have reason for despising me if your feeling corresponded to the fact in a way mine didn’t. But neither can correspond to the fact. The fact is not in itself good or bad; it is just that it thrills me but depresses you. On the other hand, 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.” This argument of Ramsey’s relied on his position on beliefs. Misak notes, “This view of the objectivity of questions about the meaning of life, and ethical questions more generally, is perfectly in line with Ramsey’s view on beliefs arrived at by inductive inference…. His point in ‘On There Being No Discussible Subject’ is that our fundamental attitudes toward life can be debated, justified, and criticized according to whether they promote or hinder human flourishing.”
Ramsey’s next seminal paper, ‘Universals’, was on the nature of particulars and universals. “Ramsey sets out and expands upon a position he discerned in Wittgenstein’s work: that we cannot solve the question of universals and particulars by doing a priori metaphysics…. Wittgenstein was confused and conflicted on the issue of the structure of logical form. Was it subject-predicate in nature? Did it have to bottom out in particular, actually existing things?” Ramsey contended, “The whole theory of particulars and universals is due to mistaking for a fundamental characteristic of reality what is merely a characteristic of language.” Misak expands, “Our language uses subject-predicate constructions, but we mustn’t be misled by that accidental fact into thinking that the entities in the world must be of two distinct types: particulars and universals. We cannot read an ontology (the nature of the world) off our language…. [In Principia,] Russell grounds the distinction of universals and particulars not on an objective but on a subjective property—the mathematician’s purposes…. Philosophers might well have other purposes.” Ramsey concluded, in agreement with Wittgenstein, “The truth is that we know and can know nothing whatever about the forms of atomic propositions.”
Ramsey was a moderate utilitarian. At the Cambridge Moral Sciences Club, the meeting’s minutes attest, Ramsey “maintained that degrees of belief were to be measured by reference to willingness to bet, and that the laws of probability were laws of consistency in partial belief, and so a generalization of formal logic. Mr. Ramsey also asserted that induction, like memory, could not be justified by formal logic or formal probability.” Ramsey thought that he had solved a major problem for utilitarians with his “general psychological theory” when he stated, “We act in the way we think most likely to realize the objects of our desire, so that a person’s actions are completely determined by his desires and opinions…. We seek things which we want, which may be our own or other people's pleasure, or anything else whatever, and our actions are such as we think most likely to realize these goods.” There are no such things as full beliefs and full desires, partial beliefs, based on our own probabilities, are the best we can hope to do. Colin Howson expounds on Ramsey’s subjective Bayesianism, “The novelty of Ramsey’s…. approach lay in regarding probabilities simply as measures of agents’ degrees of belief subject to what appears to be a rather weak consistency requirement…. [This was] a powerful new epistemology called Bayesian epistemology…. [in which] in fairly general circumstances agents with different initial, or prior, probability functions will, with enough new information, find their updated probabilities converging; in this way, it is claimed objectivity is realized as an emergent property of consistent subjective assignments.” Nils-Eric Sahlin chimes in on Ramsey’s Probability Theory, “Ramsey showed that people’s beliefs and desires can be measured with a betting method, and that given some principles of rational behaviour (e.g. that preferences are transitive) a measure of our ‘degrees of belief’ will satisfy the laws of probability. He gave us the theory of subjective probability; was the first to state the Dutch book theorem; laid the foundations of modern utility theory and decision theory; had a proof of the value of collecting evidence; took higher order probabilities seriously; and, in a derivation of ‘the rule of succession’, he introduced the notion of ‘exchangeability’. Ramsey’s theory is about as complete as any such theory can be…. Ramsey’s use of preferences among bets to quantify value differences requires the states defining the bets to be value-neutral…. Ramsey is using utilities to scale probabilities.”
Ramsey evolved into a pragmatist, who avoided reaching for claims of scientism. He stated, “The chief danger to our philosophy, apart from laziness and wooliness, is scholasticism, the essence of which is treating what is vague as if it were precise and trying to fit it into an exact logical category.” He became attracted to the pragmatist tradition founded by the American C.S. Peirce, which Ramsey described thusly, “We have… to consider the human mind and what is the most we can ask of it. The human mind works essentially according to general rules or habits…. We can therefore state the problem of the ideal as ‘What habits… would it be best for the human mind to have?’” He continues, “This is a kind of pragmatism: we judge mental habits by whether they work, i.e. whether the opinions they lead to are for the most part true, or more often true than those which alternative habits would lead to…. We are all convinced by inductive arguments, and our conviction is reasonable because the world is so constituted that inductive arguments lead on the whole to true opinions…. Induction is such a useful habit, and so to adopt it is reasonable. All that philosophy can do is analyse it, determine the degree of its utility, and find on what characteristics of nature it depends. An indispensable means for investigating these problems is induction itself, without which we should be helpless. In this circle lies nothing vicious.” Therefore, induction and memory become the “ultimate sources of knowledge.”
As his time at King’s wore on, Ramsey grew more disillusioned with his responsibilities teaching math. Misak recounts, “His work in pure mathematics was quite literally an aside. He had to prove a theorem on the way to solving a fragment of the Entscheidungsproblem in ‘On a Problem in Formal Logic’. So he stepped away from the core of his argument and proved it, in eight pages. Those eight pages are Ramsey Theory, and they are the sum total of his publications in pure mathematics. What an astounding ratio of pages to importance.”
Ramsey also paid minimal effort to economics, despite his vast contributions. His two most important papers were on optimal taxation, ‘A Contribution to the Theory of Taxation’ and the optimal savings rate for a society, ‘A Mathematical Theory of Savings’. Misak recounts, “Decades later in Cambridge, if economists employed an optimization model, they were said to be ‘doing a Ramsey’. In France the expression was ‘à la Ramsey’. When the Economic Journal celebrated its 125th anniversary with a special edition in 2015, both of Ramsey’s papers were included. That is, looking back over a century and a quarter, one of the world’s best journals of economics decided that two of its thirteen most important papers were written by Frank Ramsey when he was twenty-five years old…. Both initiated ‘entirely new fields’.” As usual, Ramsey was concerned with figuring out what was best out of what was possible, not pie in the sky speculations. Paul Samuelson would later comment that Ramsey provided “an analysis that still remains about the only substantive contribution to the theory of the second best (a subject better titled the ‘theory of the feasible fist best’).” Keynes’ obituary perhaps sums up Ramsey’s contributions to economics the best, “When he did descend from his accustomed stony heights, he still lived without effort in a rarer atmosphere than most economists care to breathe, and handled the technical apparatus of our science with the easy grace of one accustomed to something far more difficult.”
Upon Wittgenstein’s return to Cambridge from Austria, he was Ramsey’s most frequent sparring partner, with whom he argued almost daily for the last year of his life. They again parsed the Tractatus line by line, with Ramsey slowly pulling Wittgenstein away and towards a pragmatism of sorts. (Years before, as an undergraduate, Ramsey had translated the English edition of the Tractatus and was the only man Wittgenstein felt truly understood the work—a distinction he did not bestow on either Moore or Russell.) Ramsey claimed, “Philosophy must be of some use and we must take it seriously; it must be clear our thoughts and so our actions, Otherwise it is mere chatter. or else it is a disposition we have to check… i.e. the chief proposition of philosophy is that philosophy is nonsense. And again we must then take seriously that it is nonsense, and not pretend, as Wittgenstein does, that it is important nonsense!” He further ribs Wittgenstein by adding, “What we can’t say, we can’t say, and we can’t whistle it either.” (Wittgenstein would, famously, unconsciously whistle whole operas while he was lost in his thoughts.) Ramsey was objecting to the solipsism of Wittgenstein who stated, “The limits of my language mean the limits of my world.” Ramsey argued that we have to look at facts as also human and not abstract them away from human understanding. “We are forced to look not only at the objects we are talking about, but at our own mental states.” Furthermore, “We cannot really picture the world as disconnected selves; the selves we know are in the world. What we can’t do 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.” Philosophy had a subjective side that it neglected at its own peril.
At the end of his life, Ramsey was working on the fundamental nature of truth. He asserted that true beliefs were mental states with “affirmative or assertive character.” A true belief had “the felt quality… characteristic of assertion as opposed to doubt or inquiry… [and the] effects on subsequent thought and conduct.” He claimed, “A belief is true if it is a belief that p, and p.” This statement “is merely a truism, but there is no platitude so obvious that eminent philosophers have not denied it.” He continued that it was impossible to understand “truth or falsity of thoughts without considering the effects they have on our acting either directly or indirectly through dispositional beliefs.” General claims were not superfluous. “Apart from their value in simplifying our thought, they form an essential part of our mind. That we think explicitly in general terms is at the root of all praise and blame and much discussion.” Laws, rules, and general truths are needed to assess singular statements. An open generalization “expresses an inference we are at any time prepared to make, not a belief of the primary sort.” Belief can be evaluated in terms of whether it fits with experience—whether it is reliable. Beliefs “form the system with which the speaker meets the future.” Misak sums it up, “If you and I meet the future with different systems, then we disagree—we assume that the future will be compatible with one of our systems but not the other. Our beliefs are not subjective…. Knowledge… is what enables us to reliably act in the future, consolidating all our various kinds of belief. It is to be thought of in terms of good habits with which to meet the future…. We get reliability, or we increase the weight of our probabilities, by experimenting and measuring success. Probability and experimentation are at the very heart of knowledge.”
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