The attitude of the true scientist towards the real limits of human understanding was unforgettably impressed on me in early youth by the obviously unpremeditated words of a great biologist; Alfred Kuhn finished a lecture to the Austrian Academy of Science with Goethe's words, "It is the greatest joy of the man of thought to have explored the explorable and then calmly to revere the inexplorable." After the last word he hesitated, raised his hand in repudiation and cried, above the applause, "No, not calmly, gentlemen; not calmly!"

My Harvard classmate, Thomas S. Kuhn wrote, some years ago, an influential book about scientific revolutions. Fortunately, many scientific revolutions do not follow his scenario, but the one he focused on, the discovery of quantum mechanics, is well described by his model, which is most valid for a revolution occurring in the central core of a mature science.

Yes, Keynes was a genius. Yes, some of his ideas were inchoate and would not have lent themselves usefully to diagramming and symbolic manipulation. Yes, by the time of the Radcliffe committee many of his British admirers were still frozen in the Model T version of his system. And yes, Keynes resented excessive simplifying of his paradigms.
Nevertheless, in science it is not the incoherent, inchoate and ineffable that has a cash value. If that were so, Goethe would be a greater scientist than either Einstein or Newton. What matters is the Kuhnian paradigm that people who are not geniuses can use. That which so many scholars independently agreed upon cannot be independent of the text that Keynes wrote down for them to read. What is remarkable is not the cogency of the case that Leijonhufvud manages to muster, which is rather flimsy, but rather how strong was the latent demand in the 1970s for a work to debunk Keynesianism. Harry Johnson put the same point in a different way.

Kuhn's revolution was not yet a Kuhnian revolution, although he dated his intention to write the book that became Structure to the time of his wrestle with Aristotle. What he needed was a historical exemplar. He found it in the Copernican revolution.

A writer should have the precision of a poet and the imagination of a scientist.

Keynes displayed an awesome array of talents, without being preeminent in any. He was not a genius in the sense of being a Divine Fool as was Mozart or Wittgenstein ― extraordinary at one thing, babyish in everything else. He was a wonderful all-rounder, with a superbly efficient thinking machine. At Eton he had excelled at mathematics and classics, and throughout his life he effortlessly bridged the two cultures. He was not a remarkable mathematician. Nor was he a great philosopher. As a historian he was an inspired amateur. He had a theory of politics, but it never saved him from the charge of being politically naive. Keynes was great in the combination of his gifts. His achievement was to align economics with changes taking place in ethics, in culture, in politics and in society ― in a word, with the twentieth-century spirit. But, like Jevons, his qualities never quite jelled. That, rather than too great a haste, is why he failed to produce a work of art, although his writings are full of artistry. His best stylistic achievements were in his shorter pieces ― notably his biographical essays. In his big books he was the pamphleteer trying to rein in his imagination, school himself to the demands of a formal treatise. He had powerful intuitions of logical and historical relationships, but was not at his happiest in sustained argument. Like Marshall, his concentration came in short bursts. His temperament was too restless, his mind too constantly active, and bursting out with ideas and plans, for thinking in solitude.

A work of genius is a complex object and there is light to be shed about what went into the making of it. Even in the case of scientific and mathematical achievement we can say a great deal about the existing state of knowledge, the problems it failed to address, why those problems were or had become interesting, the particular capacities which the solver brought to their solution. At the other extreme is a work of art which seems to have much more immediate roots in the personal life of the artist or writer. In between is the area in which Keynes worked, which was partly scientific, partly artistic. This gives a wide justification for a biographical approach. As I put it in the introduction to my first volume: 'If underlying Keynesian theory was Keynes's vision of his age, knowledge of his state of mind and the circumstances which formed it is essential, not only in order to understand how he came to see the world as he did, but also in order to pass judgement on the theory itself.'

What truth is not, according to Kuhn, is an accurate representation of the world as it is in itself. Scientific theories represent a world, but one partially constituted by the cognitive activities of the scientists themselves. This is not a commonsensical view, but it has a distinguished philosophical pedigree, associated most strongly with Kant. The Kantian view is that the truths we can know are truths about a ‘phenomenal’ world that is the joint product of the ‘things in themselves’ and the organising, conceptual activity of the human mind.
Kuhn, however, is Kant on wheels. Where Kant held that the human contribution to the phenomenal world is invariant, Kuhn’s view is that it changes fundamentally across a scientific revolution. This is what he means by his notorious statement that, after a scientific revolution, ‘the world changes’. This is neither the trivial claim that scientists’ beliefs about the world change, nor the crazy claim that scientists can change the things in themselves simply by changing their beliefs. It is the claim that the phenomenal world changes because the human contribution to it changes.

Kuhn cannot take seriously that “there is some one full, objective, true account of nature.” Does this mean that he does not take truth seriously? Not at all. [...]
Kuhn did reject a simple “correspondence theory” which says true statements correspond to facts about the world.[...]
In the wave of skepticism that swept American scholarship at the end of the twentieth century, many influential intellectuals took Kuhn as an ally in their denials of truth as a virtue. I mean the thinkers of the sort that cannot write down or utter the word true except by literally or figuratively putting quotation marks around it—to indicate how they shudder at the very thought of so harmful a notion. Many reflective scientists, who admire much of what Kuhn says about the sciences, believe he encouraged deniers.
It is true that Structure gave enormous impetus to sociological studies of science. Some of that work, with its emphasis on the idea that facts are “socially constructed” and apparent participation in the denial of “truth,” is exactly what conservative scientists protest against. Kuhn made plain that he himself detested that development of his work...

Kuhn as does Popper rejects the idea that science grows by accumulation of eternal truths.. But while according to Popper science is ‘revolution in permanence’, and criticism the heart of the scientific enterprise, according to Kuhn revolution is exceptional and, indeed, extra-scientific, and criticism is, in ‘normal’ times, anathema... The clash between Popper and Kuhn is not about a mere technical point in epistemology. It concerns our central intellectual values, and has implications not only for theoretical physics but also for the underdeveloped social sciences and even for moral and political philosophy. If even in science there is no other way of judging a theory but by assessing the number, faith and vocal energy of its supporters, then this must be even more so in the social sciences: truth lies in power. Thus Kuhn’s position would vindicate, no doubt, unintentionally, the basic political credo of contemporary religious maniacs (‘student revolutionaries’).

After the war etching became Kirchner's favorite medium. He attributed this to its responsiveness. 'Etchings', he wrote, 'develop in the first states the most immediate hieroglyphs. Rich in lively handwriting and rich in variety of motifs, the etchings are like a diary of the painter.'

Thomas Kuhn (1962) in his book The Structure of Scientific Revolutions divides all scientists into those who create new paradigms of science and those who work within the established paradigms. The same division may be applied to scholars and philosophers, namely into those who create new paradigms and into those who work within the established ones.

When I met Wittgenstein, I saw that Schlick's warnings were fully justified. But his behavior was not caused by any arrogance. In general, he was of a sympathetic temperament and very kind; but he was hypersensitive and easily irritated. Whatever he said was always interesting and stimulating and the way in which he expressed it was often fascinating. His point of view and his attitude toward people and problems, even theoretical problems, were much more similar to those of a creative artist than to those of a scientist; one might almost say, similar to those of a religious prophet or a seer. When he started to formulate his view on some specific problem, we often felt the internal struggle that occurred in him at that very moment, a struggle by which he tried to penetrate from darkness to light under an intense and painful strain, which was even visible on his most expressive face. When finally, sometimes after a prolonged arduous effort, his answers came forth, his statement stood before us like a newly created piece of art or a divine revelation. Not that he asserted his views dogmatically … But the impression he made on us was as if insight came to him as through divine inspiration, so that we could not help feeling that any sober rational comment of analysis of it would be a profanation.

He recorded these thoughts at the instant of their birth, for a constant habit of observation and analysis had early developed with him into a second nature. His ideas were penned in the same fragmentary way as they presented themselves to his mind, perhaps with no intention of publishing them to the world. But his ideal of art depended intimately, none the less, on the system he had thrown out seemingly in so haphazard a manner. His method gives to his writings their only unity. It was more than a method: it was a permanent expression of his own life, which aided him to construct a philosophy of beauty characteristic of the new age.