Ernst Mach Quotes

Knowledge and error flow from the same mental sources; only success can tell one from the other.

By the time I began my study of physics in the early 1970s, the idea of unifying gravity with the other forces was as dead as the idea of continuous matter. It was a lesson in the foolishness of once great thinkers. Ernst Mach didn’t believe in atoms, James Clerk Maxwell believed in the aether, and Albert Einstein searched for a unified-field theory. Life is tough.

To us investigators, the concept 'soul' is irrelevant and a matter for laughter.

But we must not forget that all things in the world are connected with one another and depend on one another, and that we ourselves and all our thoughts are also a part of nature. It is utterly beyond our power to measure the changes of things by time. Quite the contrary, time is an abstraction, at which we arrive by means of the change of things; made because we are not restricted to any one definite measure, all being interconnected. A motion is termed uniform in which equal increments of space described correspond to equal increments of space described by some motion with which we form a comparison, as the rotation of the earth. A motion may, with respect to another motion, be uniform. But the question whether a motion is in itself uniform, is senseless. With just as little justice, also, may we speak of an “absolute time” --- of a time independent of change. This absolute time can be measured by comparison with no motion; it has therefore neither a practical nor a scientific value; and no one is justified in saying that he knows aught about it. It is an idle metaphysical conception.

Both [Quine and Feyerabend] want to revise a version of positivism. Quine started with the Vienna Circle, and Feyerabend with the Copenhagen school of quantum mechanics. Both the Circle and the school have been called children of Ernst Mach; if so, the philosophies of Feyerabend and Quine must be his grandchildren.

Viennese physicist Ernst Mach, for whom is named the speed of sound

Nature exists only once. It is only our schematizing reproduction that creates equal cases. It is only in those that there exists mutual dependence of certain qualities.

Die Natur ist nur einmal da. Nur unser schematisches Nachbilden erzeugt gleiche Fälle.

obviously it matters little if we think of the earth as turning about on its axis, or if we view it at rest while the fixed stars revolve around it. Geometrically these are exacly the same case of a relative rotation of the earth and the fixed stars with respect to one another.

The most important result of our reflections is …that precisely the apparently simplest mechanical theorems are of a very complicated nature; that they are founded on incomplete experiences, even on experiences that never can be fully completed; that in view of the tolerable stability of our environment they are, in fact, practically safeguarded to serve as the foundation of mathematical deduction; but that they by ho means themselves can be regarded as mathematically established truths, but only as theorems that not only admit of constant control by experience but actually require it.

The concept of absolute time—meaning a time that exists in “reality” and tick-tocks along independent of any observations of it—had been a mainstay of physics ever since Newton had made it a premise of his Principia 216 years earlier. The same was true for absolute space and distance. “Absolute, true, and mathematical time, of itself and from its own nature, flows equably without relation to anything external,” he famously wrote in Book 1 of the Principia. “Absolute space, in its own nature, without relation to anything external, remains always similar and immovable.” But even Newton seemed discomforted by the fact that these concepts could not be directly observed. “Absolute time is not an object of perception,” he admitted. He resorted to relying on the presence of God to get him out of the dilemma. “The Deity endures forever and is everywhere present, and by existing always and everywhere, He constitutes duration and space.”45 Ernst Mach, whose books had influenced Einstein and his fellow members of the Olympia Academy, lambasted Newton’s notion of absolute time as a “useless metaphysical concept” that “cannot be produced in experience.” Newton, he charged, “acted contrary to his expressed intention only to investigate actual facts.”46 Henri Poincaré also pointed out the weakness of Newton’s concept of absolute time in his book Science and Hypothesis, another favorite of the Olympia Academy. “Not only do we have no direct intuition of the equality of two times, we do not even have one of the simultaneity of two events occurring in different places,” he wrote.

Mach dir keinen Kummer, ich werde dich lieben und dir die schrecklichen Sachen ersparen, von denen dir deine Schulfreundinnen erzählen: Sachen, wie sie angeblich in Hochzeitsnächten passieren; glaub dem Geflüster dieser Närrinnen nicht; wir werden lachen, wenn es soweit ist, bestimmt, ich verspreche es dir, aber du mußt noch warten, ein paar Wochen, höchstens einen Monat, bis ich den Blumenstrauß kaufen, die Droschke mieten, vor eurem Haus vorfahren kann. Wir werden reisen, uns die Welt anschauen, du wirst mir Kinder schenken, fünf, sechs, sieben; die Kinder werden mir Enkel schenken, fünfmal, sechsmal, siebenmal sieben; du wirst nie merken, daß ich arbeite; ich werde dir den Männerschweiß ersparen, Muskelernst und Uniformernst; alles geht mir leicht von der Hand, ich hab's gelernt, ein bißchen studiert, hab den Schweiß im voraus bezahlt; ich bin kein Künstler; mach dir keine Illusionen; ich werde dir weder falsche noch echte Dämonie bieten können, das wovon dir deine Freundinnen Gruselmärchen erzählen, werden wir nicht im Schlafzimmer tun, sondern im Freien: du sollst den Himmel über dir sehen. Blätter oder Gräser sollen dir ins Gesicht fallen, du sollst den Geruch eines Herbstabends schmecken und nicht das Gefühl haben, an einer widerwärtigen Turnübung teilzunehmen, zu der du verpflichtet bist; du sollst herbstliches Gras riechen, wir werden im Sand liegen, unten am Flußufer, zwischen den Weidenbüschen, gleich oberhalb der Spur, die das Hochwasser hinterließ; Schlifstengel, Korken, Schuhkremdosen, eine Rosenkranzperle, die einer Schifferfrau über Bord fiel, und in einer Limonadenflasche eine Post; in der Luft der bittere Rauch der Schiffsschornsteine; rasselnde Ankerketten; wir werden keinen blutigen Ernst draus machen, obwohl's natürlich ernst und blutig ist".

While Einstein was still a patent clerk he had studied the work of the Austrian physicist Ernst Mach, for whom the goal of science was not to discern the nature of reality, but to describe experimental data, the 'facts', as economically as possible.

His nemesis, the physicist turned philosopher Ernst Mach, maintained that science should focus only on relationships among directly observable quantities.

In aeronautics, the Mach number (named after the German physicist Ernst Mach) is the ratio of object speed to the speed of sound. At sea level (and at 20°C), sound travels 340 m/s, or about 1,224 km/h; the speed of sound declines slightly with altitude, and at 11 kilometers above sea level, a typical cruising altitude for jetliners, it is about 295 m/s or 1,063 km/h, and hence a Boeing 787 cruising at 903 km/h will fly at M 0.85. All speeds of M < 1 are subsonic; transonic is the term used for speed in the vicinity of M, and the supersonic range is 1 < M < 3.

Anyone who has in mind the gathering up of the sciences into a single whole, has to look for a conception to which he can hold in every department of science. Now if we resolve the whole material world into elements which are at the same time also elements of the psychical world and, as such, are also commonly called sensation, if, further, we regard it as the sole task of science to inquire into the connexion and combination of these elements, which are of the same nature in all departments, and into their mutual dependence on each other; we may then reasonably expect to build a unifed monistic structure upon this conception, and thus to get rid of the distressing confusions of dualism.

Above all there is no Machist philosophy. At most [there is] a scientific methodology and a psychology of knowledge [Erkenntnispsychologie]; and like all scientific theories both are provisional and imperfect efforts. I am not responsible for the philosophy which can be constructed from these with the help of extraneous ingredients... . The land of the transcendental is closed to me.

Above all there is no Machist philosophy. At most [there is] a scientific methodology and a psychology of knowledge [Erkenntnispsychologie]; and like all scientific theories both are provisional and imperfect efforts. I am not responsible for the philosophy which can be constructed from these with the help of extraneous ingredients….The land of the transcendental is closed to me. And if I make the open confession that its inhabitants are not able at all to excite my curiosity, then you may estimate the wide abyss that exists between me and many philosophers. For this reason I already have declared explicitly that I am by no means a philosopher, but only a scientist. If nevertheless occasionally, and in a somewhat noisy way, I have been listed among the former then I am not responsible for this. Of course, I also do not want to be a scientist who blindly entrusts himself to the guidance of a single philosopher in the way that Moliere’s physician I expected and demanded of his patients.

The philosopher Ernst Mach once got on a bus, and saw a scruffy unkempt bookish-looking person at the far end. He thought to himself (1) That man is a shabby pedagogue. In fact, Mach was seeing himself in a large mirror at the far end of the bus, of the sort conductors used to help keep track of things. He eventually realized this, and thought to himself: (2) I am that man. (3) I am a shabby pedagogue.

What is meant by 'position' in the quantum realm? Nothing more or less, Heisenberg answered, than the result of a specific experiment designed to measure, say, the 'position of the electron' in space at a given moment, 'otherwise this word has no meaning'.46 For him there simply is no electron with a well-defined position or a well-defined momentum in the absence of an experiment to measure its position or momentum. A measurement of an electron's position creates an electron-with-a-position, while a measurement of its momentum creates an electron-with-a-momentum. The very idea of an electron with a definite 'position' or 'momentum' is meaningless prior to an experiment that measures it. Heisenberg had adopted an approach to defining concepts through their measurement that harked back to Ernst Mach and what philosophers called operationalism. But it was more than just a redefinition of old concepts.

Il grande scienziato è come un capo di esercito che non si attarda, per ogni postazione strappata ai nemici, a compiere meticolose ricerche sul diritto di occuparla. La grandezza delle imprese da compiere non gliene lascia il tempo. Per coloro che vengono dopo, la cosa è diversa. Newton ha dovuto aspettare che i due secoli a lui successivi esaminassero di nuovo e confermassero i fondamenti dei suoi lavori. Accade infatti che al tempo delle nuove scoperte segua un periodo di maggiore stabilità per le scienze. Allora i principi sono oggetto di un interesse filosofico più vivo che non ciò che è dedotto da essi. Vengono così poste questioni del tipo di quelle qui trattate, alla cui soluzione ci auguriamo di aver dato un piccolo contributo. Condividiamo con l'eminente fisico W. Thomson (Lord Kelvin) la più grande ammirazione per Newton, non però il parere che l'esposizione newtoniana sia ancora oggi la migliore possibile e la più filsofica.

Ernst Mach for example considered that the visual, tactile, and auditory modes each defined a particular “space” and that these spaces furthermore were the physiological origin of conceptions of geomet- rical and phenomenal space.⁸ Mach considered that the notion of “surface” has a similar source: our own skin. He wrote, “The space of the skin is the analog of a two-dimensional, finite, unbounded and closed Riemannian space.”⁹ For Mach, all symmetry was derived from the left and right orientation of the human body. Even the Cartesian coordinates (x, y) had their origin in this corporeal schema.

The new scientific outlook of Darwin’s evolution and Ernst Mach’s physics had demonstrated to all concerned that there was no heaven above, only an open, empty sky.‡ “Metaphysical reality” was a self-contradiction.12 Science had left Western man standing alone on an empty train platform, with all the emotional and intellectual baggage left by a Christianity that had been based on a myth and had absorbed a lie: Plato’s assertion that man had a “higher” rational self, when all it was was his own fear of life.

Ernst Mach held to the conviction that all great contributions to science, all great theories, were not so much closer approximations to a final description of reality as they were insights into the psychology of the scientists who produced them. In this view, the history of science is really the history of a succession of individual psychologies writ large, as it were, a notion suggesting perhaps that some scientific theories at least might be considered psychopathological. A world- view that idealizes the “pleromatic” as composed of dead, mindless matter has be- come reified into a world in which the reality of the death of ecosystems has be- come all too apparent. One hypothesizes that the thinking of Hoffmeyer, Bateson, and Serres represents a reaction to what they see as the psychopathology inherent in the excesses of modern science. As opposed to this way of thinking, each of the foregoing thinkers has attempted to provide a rational (in the Platonic sense) re- description of the grounds on which future scientific theorizations should develop. This perhaps represents the beginnings of an (unknowingly) rediscovered imag- inary that supplants one of actants over and against objects and ideals of algorithmic certainty of outcome, with one of intersubjective exchanges governed by the mystery of probability, negentropy, and difference.

Indeed, if the goal of philosophy has become to use reason to defend the irrational or to accept arguments on other grounds than probable truth, then perhaps it is no more than apologetics and may well deserve the scorn which many practical people direct at it.