giovedì 25 maggio 2017

Il consenso come morte della scianza

The Scientist as Rebel (New York Review Books (Paperback)) by Freeman Dyson
La posizione riduzionista è una posizione filosofica, non scientifica. E lo scienziato più autentico è più un poeta che un filosofo di tipo particolare.
In questo senso il riduzionismo mal si coniuga con la scienza.
Si parla spesso di “comunità scientifica”. L’espressione andrebbe usata con cautela poiché il consenso è la morte della scienza
… THERE IS NO such thing as a unique scientific vision, any more than there is a unique poetic vision. Science is a mosaic of partial and conflicting visions…
La scienza è tante cose. Tante cose che hanno un solo tratto in comune: lo spirito critico e lo spirito di sfida…
… But there is one common element in these visions. The common element is rebellion against the restrictions imposed by the locally prevailing culture…
La scienza è anarchica, non rispetta nessuno…
… One of the central facts about science is that it pays no attention to East and West and North and South and black and yellow and white….
Omar Khayyam, il ribelle…
… For the great Arab mathematician and astronomer Omar Khayyam, science was a rebellion against the intellectual constraints of Islam…
La ribellione della scienza giapponese
… For the first generations of Japanese scientists in the nineteenth century, science was a rebellion against their traditional culture of feudalism…
La ribellione della scienza indiana
… For the great Indian physicists of this century, Raman, Bose, and Saha, science was a double rebellion, first against English domination and second against the fatalistic ethic of Hinduism…
Galileo e Einstein, due ribelli…
… scientists from Galileo to Einstein have been rebels. Here is how Einstein himself described the situation: When I was in the seventh grade at the Luitpold Gymnasium in Munich, I was summoned by my home-room teacher who expressed the wish that I leave the school. To my remark that I had done nothing amiss, he replied only, “Your mere presence spoils the respect of the class for me.”…
Einstein abbandonò la scuola a 15 anni! Una forma di ribellione.
La scienza come alleanza tra spiriti liberi.
La scienza va alla sostanza dell’uomo: siamo tutti africani… siamo tutti anfibi…
… Over a time span of 100,000 years we are all Africans. And over a time span of 300 million years we are all amphibians, waddling uncertainly out of dried-up ponds onto the alien and hostile land…
La scienza mette in primo piano la natura travalicando le culture…
… Ironic, detached, contemptuous like Einstein of national pride and cultural taboos, he stood in awe of nature alone…
La scienza non rispetta nulla, in primo luogo non rispetta la cultura.
La scienza è razzista, misogina, omofoba, guerrafondaia… non si cura di nulla.
Non esiste una scienza orientale o occidentale.
Non esiste un legame tra scienza e cultura perché la scienza è mancato rispetto della cultura e dei suoi riti.
Se la scienza ha trovato dei luoghi più adatti dove diffondersi è perché quei luoghi hanno promosso l’individualismo e la critica, ovvero ha tenuto aperte delle aree di non-rispetto della comunità.
Se queste sono le premesse, è normale che la scienza finisca spesso in prigione
… In our century we have seen the physicist Lev Landau sitting in jail in the Soviet Union and Pyotr Kapitsa risking his own life by appealing to Stalin to let Landau out. We have seen the mathematician André Weil sitting in jail in Finland during the Winter War of 1939–1940 and Lars Ahlfors saving his life… Another example of science as subversion is Andrei Sakharov. Davis and Sakharov belong to an old tradition in science that goes all the way back to the rebels Benjamin Franklin and Joseph Priestley in the eighteenth century, to Galileo and Giordano Bruno in the seventeenth and sixteenth…
Haldane: il prototipo dello scienziato ribelle…
… The vision of science as rebellion was articulated in Cambridge with great clarity on February 4, 1923, in a lecture by the biologist J.B. S. Haldane to the Society of Heretics. The lecture was published as a little book with the title Daedalus…
***
Tuttavia, c’è chi vive la scienza come il mito dell’unificazione del sapere. Chi sogna una scienza che descriva tutto con poche equazioni. E’ il riduzionista.
Per lui tutto puo’ e deve essere ridotto ad un rigo scritto su un foglio di carta. E’ questa la sua fede.
Ma il riduzionismo ha fallito clamorosamente nel XX secolo. Ha fallito per esempio nella matematica (vedi Godel)…
… I have already made it clear that I have a low opinion of reductionism, which seems to me to be at best irrelevant and at worst misleading as a description of what science is about. Let me begin with pure mathematics. Here the failure of reductionism has been demonstrated by rigorous proof. This will be a familiar story to many of you…. Gödel proved that in any formulation of mathematics, including the rules of ordinary arithmetic, a formal process for separating statements into true and false cannot exist… To decide whether a mathematical statement is true, it is not sufficient to reduce the statement to marks on paper and to study the behavior of the marks…
Ma c’è di più: la fissa riduzionista rende sterile lo scienziato…
… It is a curious paradox that several of the greatest and most creative spirits in science, after achieving important discoveries by following their unfettered imaginations, were in their later years obsessed with reductionist philosophy and as a result became sterile…
Qui si presenta il triste caso di Einstein anziano, che causa bias riduzionista non fu mai in grado di accettare la meccanica quantistica.
Fino ai suoi quarant’anni questo bias non l’afflisse!… Poi fu colto dal demone della bella equazione e dell’ “unità” a tutti i costi…
… Like Hilbert, Einstein did his great work up to the age of forty without any reductionist bias… But like Hilbert, as he grew older he concentrated his attention more and more on the formal properties of his equations, and he lost interest in the wider universe of ideas out of which the equations arose. His last twenty years were spent in a fruitless search for a set of equations that would unify the whole of physics, without paying attention to the rapidly proliferating experimental discoveries that any unified theory would finally have to explain. I do not need to say more about this tragic and well-known story of Einstein’s lonely attempt to reduce physics to a finite set of marks on paper…
Ma il bias fu responsabile di un’incomprensione forse ancora più clamorosa e meno nota: Einstein non accettò mai l’esistenza dei buchi neri
… I shall instead discuss another aspect of Einstein’s later life, an aspect that has received less attention than his quest for the unified field equations: his extraordinary hostility to the idea of black holes…
Gli scopritori dei buchi neri: Robert Oppenheimer and Hartland Snyder…
… Oppenheimer and Snyder found solutions of Einstein’s equations that described what happens to a massive star when it has exhausted its supplies of nuclear energy. The star collapses gravitationally and disappears from the visible universe, leaving behind only an intense gravitational field to mark its presence…
I buchi neri sono stati teorizzati ma anche in qualche modo verificati
… We now know that black holes ranging in mass from a few suns to a few billion suns actually exist…
Einstein alzò subito un muro: se i fatti non mi soddisfano, peggio per i fatti. L’equazione va salvata, ecco quello che conta…
… Einstein was not merely skeptical, he was actively hostile to the idea of black holes. He thought that the black hole solution was a blemish to be removed from his theory by a better mathematical formulation, not a consequence to be tested by observation… To discover the right equations was all that mattered…
L’ossessione per la legge generale e astratta rende ciechi.
Con questo non si vuole dire che il riduzionismo non vanti anche dei successi…
… In the history of science it happens not infrequently that a reductionist approach leads to a spectacular success… sometimes the understanding of a whole field of science is suddenly advanced by the discovery of a single basic equation. Thus it happened that the Schrödinger equation in 1926 and the Dirac equation in 1927 brought a miraculous order into the previously mysterious processes of atomic physics… Bewildering complexities of chemistry and physics were reduced to two lines of algebraic symbols…
Ma spesso, troppo spesso, la comprensione non coincide con la generalizzazione. In questo senso ridurre non è fare scienza…
… But it happens at least equally often in the history of science that the understanding of the component parts of a composite system is impossible without an understanding of the behavior of the system as a whole. And it often happens that the understanding of the mathematical nature of an equation is impossible without a detailed understanding of its solutions. The black hole is a case in point…
Il riduzionismo è filosofia, la scienza è arte.
Le cattedrali di Godel…
… When I look at Gödel’s proof of his undecidability theorem, I do not see a philosophical argument. The proof is a soaring piece of architecture, as unique and as lovely as Chartres Cathedral… It is a construction, not a reduction… Gödel proved that in mathematics the whole is always greater than the sum of the parts…
Oppure, l’arte concettuale dei buchi neri…
… The black hole solution of Einstein’s equations is also a work of art. The black hole is not as majestic as Gödel’s proof, but it has the essential features of a work of art: uniqueness, beauty, and unexpectedness…
***
Quando uno scienziato lavora non segue un metodo
… When I am working, I feel myself to be practicing a craft rather than following a method… I had consciously in mind a metaphor…
Si fa guidare dalle metafore che ha in testa, come un artista…
***
La storia della scienza è divisa in due correnti: 1) coloro per cui contano le forze sociali e 2) coloro per cui contano i metodi. Propongo una terza via: 3) coloro per cui conta l’individuo (libero sia dalle spinte sociali che dai metodi trascendenti)…
… In recent years there has been great dispute among historians of science, some believing that science is driven by social forces, others believing that science transcends social forces and is driven by its own internal logic and by the objective facts of nature. Historians of the first group write social history, those of the second group write intellectual history. Since I believe that scientists should be artists and rebels, obeying their own instincts rather than social demands or philosophical principles, I do not fully agree with either view of history…
Lo scienziato è un uomo: come perfetto truth-seekers non è credibile…
… The image of noble and virtuous dedication to truth, the image that scientists have traditionally presented to the public, is no longer credible… Historians who believe in the transcendence of science have portrayed scientists as living in a transcendent world of the intellect, superior to the transient, corruptible, mundane realities of the social world…
La scienza non è una teoria filosofica coerente ma un accrocchio spesso contraddittorio di saperi diversificati… c’è spazio un po’ per tutti…
… Both in science and in history there is room for a variety of styles and purposes. There is no necessary contradiction between the transcendence of science and the realities of social history… To my mind, the history of science is most illuminating when the frailties of human actors are put into juxtaposition with the transcendence of nature’s laws…
Anche coltivare teorie poco promettenti è giustificato. Molta conoscenza che oggi diamo per scontata un tempo si presentava come teoria poco promettente difficile da verificare.
***
Come avanza la scienza? Non perché ben inquadrata grazie a una buona filosofia di fondo (come il riduzionismo)…
… Science is an art form and not a philosophical method. The great advances in science usually result from new tools rather than from new doctrines….
Il riduzionismo fa male alla scienza perché non è altro che una filosofia. in questo senso la ingabbia…
… If we try to squeeze science into a single philosophical viewpoint such as reductionism, we are like Procrustes chopping off the feet of his guests when they do not fit onto his bed….