In philosophy of science, confirmation holism, also called epistemological holism, is the view that no individual statement can be confirmed or disconfirmed by an empirical test, but rather that only a set of statements (a whole theory) can be so. It is attributed to Willard Van Orman Quine who motivated his holism through extending Pierre Duhem's problem of underdetermination in physical theory to all knowledge claims. [1] [2]
Duhem's idea was, roughly, that no theory of any type can be tested in isolation but only when embedded in a background of other hypotheses, e.g. hypotheses about initial conditions. Quine thought that this background involved not only such hypotheses but also our whole web of belief, which, among other things, includes our mathematical and logical theories and our scientific theories. This last claim is sometimes known as the Duhem–Quine thesis. [3]
A related claim made by Quine, though contested by some (see Adolf Grünbaum 1962), [4] is that one can always protect one's theory against refutation by attributing failure to some other part of our web of belief. In his own words, "Any statement can be held true come what may, if we make drastic enough adjustments elsewhere in the system." [1]
By 1845 astronomers found that the orbit of planet Uranus around the Sun departed from expectations. Not concluding that Newton's law of universal gravitation was flawed, however, astronomers John Couch Adams as well as Urbain Le Verrier independently predicted a new planet, eventually known as Neptune, and even calculated its weight and orbit through Newton's theory. [lower-alpha 1] And yet neither did this empirical success of Newton's theory verify Newton's theory.
Le Verrier soon reported that Mercury's perihelion—the peak of its orbital ellipse nearest to the Sun—advanced each time Mercury completed an orbit, a phenomenon not predicted by Newton's theory, which astrophysicists were so confident in that they predicted a new planet, named Vulcan , which a number of astronomers subsequently claimed to have seen. In 1905, however, Einstein's special theory of relativity claimed that space and time are both relative, refuting the very framework of Newton's theory that claimed that space and time were both absolute.
In 1915, Einstein's general theory of relativity newly explained gravitation while precisely predicting Mercury's orbit. In 1919, astrophysicist Arthur Eddington led an expedition to test Einstein's prediction of the Sun's mass reshaping spacetime in its vicinity. The Royal Society announced confirmation—accepted by physicists as the fall of Newton's theory. Yet few theoretical physicists believe general relativity is a fundamentally accurate description of gravitation, and instead seek a theory of quantum gravity. [6] [7] [ citation needed ]
Some scholars, like Quine, argue that if a prediction that a theory makes comes out true, then the corresponding piece of evidence confirms the whole theory and even the whole framework within which that theory is embedded. Some have questioned this radical or total form of confirmational holism. If total holism were true, they argue, that would lead to absurd consequences like the confirmation of arbitrary conjunctions. For example, if the general theory of relativity is confirmed by the perihelion of Mercury then, according to total holism, the conjunction of the general theory of relativity with the claim that the moon is made of cheese also gets confirmed. More controversially, the two conjuncts are meant to be confirmed in equal measure.
The critics of total holism do not deny that evidence may spread its support far and wide. Rather, they deny that it always spreads its support to the whole of any theory or theoretical framework that entails or probabilistically predicts the evidence. This view is known as partial holism. One early advocate of partial confirmational holism is Adolf Grünbaum (1962). [4] Another is Ken Gemes (1993). [8] The latter provides refinements to the hypothetico-deductive account of confirmation, arguing that a piece of evidence may be confirmationally relevant only to some content parts of a hypothesis. A third critic is Elliott Sober (2004). [9] He considers likelihood comparisons and model selection ideas. More recently, and in a similar vein, Ioannis Votsis (2014) [10] argues for an objectivist account of confirmation, according to which, monstrous hypotheses, i.e. roughly hypotheses that are put together in an ad hoc or arbitrary way, have internal barriers that prevent the spread of confirmation between their parts. Thus even though the conjunction of the general theory of relativity with the claim that the moon is made of cheese gets confirmed by the perihelion of Mercury since the latter is entailed by the conjunction, the confirmation does not spread to the conjunct that the moon is made of cheese. In other words, it is not always the case that support spreads to all the parts of a hypotheses, and even when it does, it is not always the case that it spreads to the different parts in equal measure.
The theory of relativity usually encompasses two interrelated physics theories by Albert Einstein: special relativity and general relativity, proposed and published in 1905 and 1915, respectively. Special relativity applies to all physical phenomena in the absence of gravity. General relativity explains the law of gravitation and its relation to the forces of nature. It applies to the cosmological and astrophysical realm, including astronomy.
In physics, gravity (from Latin gravitas 'weight') is a fundamental interaction which causes mutual attraction between all things that have mass. Gravity is, by far, the weakest of the four fundamental interactions, approximately 1038 times weaker than the strong interaction, 1036 times weaker than the electromagnetic force and 1029 times weaker than the weak interaction. As a result, it has no significant influence at the level of subatomic particles. However, gravity is the most significant interaction between objects at the macroscopic scale, and it determines the motion of planets, stars, galaxies, and even light.
Vulcan was a theorized planet that some pre-20th century astronomers thought existed in an orbit between Mercury and the Sun. Speculation about, and even purported observations of, intermercurial bodies or planets date back to the beginning of the 17th century. The case for their probable existence was bolstered by the French mathematician who had used disturbances in the orbit of Uranus to predict the existence of planet Neptune, Urbain Le Verrier. By 1859 he had confirmed unexplained peculiarities in Mercury's orbit and predicted they had to be the result of gravitational influences of another unknown nearby planet or series of asteroids. A French amateur astronomer's report that he had observed an object passing in front of the Sun that same year led Le Verrier to announce that the long sought after planet, which he gave the name Vulcan, had been discovered at last.
A scientific theory is an explanation of an aspect of the natural world and universe that can be repeatedly tested and corroborated in accordance with the scientific method, using accepted protocols of observation, measurement, and evaluation of results. Where possible, some theories are tested under controlled conditions in an experiment. In circumstances not amenable to experimental testing, theories are evaluated through principles of abductive reasoning. Established scientific theories have withstood rigorous scrutiny and embody scientific knowledge.
Newton's law of universal gravitation says that every particle attracts every other particle in the universe with a force that is proportional to the product of their masses and inversely proportional to the square of the distance between their centers. Separated objects attract and are attracted as if all their mass were concentrated at their centers. The publication of the law has become known as the "first great unification", as it marked the unification of the previously described phenomena of gravity on Earth with known astronomical behaviors.
The hypothetico-deductive model or method is a proposed description of the scientific method. According to it, scientific inquiry proceeds by formulating a hypothesis in a form that can be falsifiable, using a test on observable data where the outcome is not yet known. A test outcome that could have and does run contrary to predictions of the hypothesis is taken as a falsification of the hypothesis. A test outcome that could have, but does not run contrary to the hypothesis corroborates the theory. It is then proposed to compare the explanatory value of competing hypotheses by testing how stringently they are corroborated by their predictions.
Pierre Maurice Marie Duhem was a French theoretical physicist who worked on thermodynamics, hydrodynamics, and the theory of elasticity. Duhem was also a historian of science, noted for his work on the European Middle Ages, which is regarded as having created the field of the history of medieval science. As a philosopher of science, he is remembered principally for his views on the indeterminacy of experimental criteria.
In science, an experimentum crucis is an experiment capable of decisively determining whether or not a particular hypothesis or theory is superior to all other hypotheses or theories whose acceptance is currently widespread in the scientific community. In particular, such an experiment must typically be able to produce a result that rules out all other hypotheses or theories if true, thereby demonstrating that under the conditions of the experiment, those hypotheses and theories are proven false but the experimenter's hypothesis is not ruled out.
General relativity is a theory of gravitation developed by Albert Einstein between 1907 and 1915. The theory of general relativity says that the observed gravitational effect between masses results from their warping of spacetime.
In the philosophy of science, underdetermination or the underdetermination of theory by data is the idea that evidence available to us at a given time may be insufficient to determine what beliefs we should hold in response to it. The underdetermination thesis says that all evidence necessarily underdetermines any scientific theory.
Tests of general relativity serve to establish observational evidence for the theory of general relativity. The first three tests, proposed by Albert Einstein in 1915, concerned the "anomalous" precession of the perihelion of Mercury, the bending of light in gravitational fields, and the gravitational redshift. The precession of Mercury was already known; experiments showing light bending in accordance with the predictions of general relativity were performed in 1919, with increasingly precise measurements made in subsequent tests; and scientists claimed to have measured the gravitational redshift in 1925, although measurements sensitive enough to actually confirm the theory were not made until 1954. A more accurate program starting in 1959 tested general relativity in the weak gravitational field limit, severely limiting possible deviations from the theory.
The deductive-nomological model of scientific explanation, also known as Hempel's model, the Hempel–Oppenheim model, the Popper–Hempel model, or the covering law model, is a formal view of scientifically answering questions asking, "Why...?". The DN model poses scientific explanation as a deductive structure, one where truth of its premises entails truth of its conclusion, hinged on accurate prediction or postdiction of the phenomenon to be explained.
General relativity is a theory of gravitation that was developed by Albert Einstein between 1907 and 1915, with contributions by many others after 1915. According to general relativity, the observed gravitational attraction between masses results from the warping of space and time by those masses.
The indeterminacy of translation is a thesis propounded by 20th-century American analytic philosopher W. V. Quine. The classic statement of this thesis can be found in his 1960 book Word and Object, which gathered together and refined much of Quine's previous work on subjects other than formal logic and set theory. The indeterminacy of translation is also discussed at length in his Ontological Relativity. Crispin Wright suggests that this "has been among the most widely discussed and controversial theses in modern analytical philosophy". This view is endorsed by Hilary Putnam, who states that it is "the most fascinating and the most discussed philosophical argument since Kant's Transcendental Deduction of the Categories".
In philosophy of science, the Duhem–Quine thesis, also called the Duhem–Quine problem, posits that it is impossible to experimentally test a scientific hypothesis in isolation, because an empirical test of the hypothesis requires one or more background assumptions : the thesis says that unambiguous scientific falsifications are impossible. It is named after French theoretical physicist Pierre Duhem and American logician Willard Van Orman Quine, who wrote about similar concepts.
In theoretical physics, Whitehead's theory of gravitation was introduced by the mathematician and philosopher Alfred North Whitehead in 1922. While never broadly accepted, at one time it was a scientifically plausible alternative to general relativity. However, after further experimental and theoretical consideration, the theory is now generally regarded as obsolete.
In physics, theories of gravitation postulate mechanisms of interaction governing the movements of bodies with mass. There have been numerous theories of gravitation since ancient times. The first extant sources discussing such theories are found in ancient Greek philosophy. This work was furthered through the Middle Ages by Indian, Islamic, and European scientists, before gaining great strides during the Renaissance and Scientific Revolution—culminating in the formulation of Newton's law of gravity. This was superseded by Albert Einstein's theory of relativity in the early 20th century.
In classical theories of gravitation, the changes in a gravitational field propagate. A change in the distribution of energy and momentum of matter results in subsequent alteration, at a distance, of the gravitational field which it produces. In the relativistic sense, the "speed of gravity" refers to the speed of a gravitational wave, which, as predicted by general relativity and confirmed by observation of the GW170817 neutron star merger, is equal to the speed of light (c).
Paul Gerber was a German physics teacher. He studied in Berlin from 1872 to 1875. In 1877 he became a teacher at the Realgymnasium in Stargard in Pommern. Gerber is known for his controversial work on the speed of gravity and the perihelion shift of Mercury's orbit.
Evidence for a proposition is what supports the proposition. It is usually understood as an indication that the supported proposition is true. What role evidence plays and how it is conceived varies from field to field.