Philosophy is the study of general and fundamental questions about existence, values, reason and language. Such questions are posed as problems to be studied or resolved; the term was coined by Pythagoras. Philosophical methods include questioning, critical discussion, rational argument, systematic presentation. Classic philosophical questions include: Is it possible to know anything and to prove it? What is most real? Philosophers pose more practical and concrete questions such as: Is there a best way to live? Is it better to be just or unjust? Do humans have free will? "philosophy" encompassed any body of knowledge. From the time of Ancient Greek philosopher Aristotle to the 19th century, "natural philosophy" encompassed astronomy and physics. For example, Newton's 1687 Mathematical Principles of Natural Philosophy became classified as a book of physics. In the 19th century, the growth of modern research universities led academic philosophy and other disciplines to professionalize and specialize.
In the modern era, some investigations that were traditionally part of philosophy became separate academic disciplines, including psychology, sociology and economics. Other investigations related to art, politics, or other pursuits remained part of philosophy. For example, is beauty objective or subjective? Are there many scientific methods or just one? Is political utopia a hopeful dream or hopeless fantasy? Major sub-fields of academic philosophy include metaphysics, ethics, political philosophy and philosophy of science. Traditionally, the term "philosophy" referred to any body of knowledge. In this sense, philosophy is related to religion, natural science and politics. Newton's 1687 Mathematical Principles of Natural Philosophy is classified in the 2000s as a book of physics. In the first part of the first book of his Academics, Cicero introduced the division of philosophy into logic and ethics. Metaphysical philosophy was the study of existence, God, logic and other abstract objects; this division has changed.
Natural philosophy has split into the various natural sciences astronomy, chemistry and cosmology. Moral philosophy still includes value theory. Metaphysical philosophy has birthed formal sciences such as logic and philosophy of science, but still includes epistemology and others. Many philosophical debates that began in ancient times are still debated today. Colin McGinn and others claim. Chalmers and others, by contrast, see progress in philosophy similar to that in science, while Talbot Brewer argued that "progress" is the wrong standard by which to judge philosophical activity. In one general sense, philosophy is associated with wisdom, intellectual culture and a search for knowledge. In that sense, all cultures and literate societies ask philosophical questions such as "how are we to live" and "what is the nature of reality". A broad and impartial conception of philosophy finds a reasoned inquiry into such matters as reality and life in all world civilizations. Western philosophy is the philosophical tradition of the Western world and dates to Pre-Socratic thinkers who were active in Ancient Greece in the 6th century BCE such as Thales and Pythagoras who practiced a "love of wisdom" and were termed physiologoi.
Socrates was a influential philosopher, who insisted that he possessed no wisdom but was a pursuer of wisdom. Western philosophy can be divided into three eras: Ancient, Medieval philosophy, Modern philosophy; the Ancient era was dominated by Greek philosophical schools which arose out of the various pupils of Socrates, such as Plato, who founded the Platonic Academy and his student Aristotle, founding the Peripatetic school, who were both influential in Western tradition. Other traditions include Cynicism, Greek Skepticism and Epicureanism. Important topics covered by the Greeks included metaphysics, the nature of the well-lived life, the possibility of knowledge and the nature of reason. With the rise of the Roman empire, Greek philosophy was increasingly discussed in Latin by Romans such as Cicero and Seneca. Medieval philosophy is the period following the fall of the Western Roman Empire and was dominated by the ris
Pierre Maurice Marie Duhem was a French theoretical physicist who worked on thermodynamics and the theory of elasticity. Duhem was a historian of science, noted for his work on the European Middle Ages; as a philosopher of science, he is remembered principally for his views on the indeterminacy of experimental criteria. Among scientists, Duhem is best known today for his work on chemical thermodynamics, in particular for the Gibbs–Duhem and Duhem–Margules equations, his approach was influenced by the early works of Josiah Willard Gibbs, which Duhem explicated and promoted among French scientists. In continuum mechanics, he is remembered for his contribution to what is now called the Clausius–Duhem inequality. Duhem was convinced that all physical phenomena, including mechanics and chemistry, could be derived from the principles of thermodynamics. Influenced by Macquorn Rankine's "Outlines of the Science of Energetics", Duhem carried out this intellectual project in his Traité de l'Énergétique, but was unable to reduce electromagnetic phenomena to thermodynamic first principles.
With Ernst Mach, Duhem shared a skepticism about the usefulness of the concept of atoms. He therefore did not follow the statistical mechanics of Maxwell and Gibbs, who explained the laws of thermodynamics in terms of the statistical properties of mechanical systems composed of many atoms. Duhem is well known for his work on the history of science, which resulted in the ten volume Le système du monde: histoire des doctrines cosmologiques de Platon à Copernic. Unlike many former historians, who denigrated the Middle Ages, he endeavored to show that the Roman Catholic Church had helped foster Western science in one of its most fruitful periods, his work in this field was prompted by his research into the origins of statics, where he encountered the works of medieval mathematicians and philosophers such as John Buridan, Nicole Oresme and Roger Bacon, whose sophistication surprised him. He came to regard them as the founders of modern science, having in his view anticipated many of the discoveries of Galileo Galilei and thinkers.
Duhem concluded that "the mechanics and physics of which modern times are justifiably proud to proceed, by an uninterrupted series of scarcely perceptible improvements, from doctrines professed in the heart of the medieval schools." Duhem popularized the concept of "saving the phenomena." In addition to the Copernican Revolution debate of "saving the phenomena" versus offering explanations that inspired Duhem was Thomas Aquinas, who wrote, regarding eccentrics and epicycles, thatReason may be employed in two ways to establish a point: firstly, for the purpose of furnishing sufficient proof of some principle. Reason is employed in another way, not as furnishing a sufficient proof of a principle, but as confirming an established principle, by showing the congruity of its results, as in astronomy the theory of eccentrics and epicycles is considered as established, because thereby the sensible appearances of the heavenly movements can be explained. Duhem's views on the philosophy of science are explicated in his 1906 work The Aim and Structure of Physical Theory.
In this work, he opposed Newton's statement that the Principia's law of universal mutual gravitation was deduced from'phenomena', including Kepler's second and third laws. Newton's claims in this regard had been attacked by critical proof-analyses of the German logician Leibniz and most famously by Immanuel Kant, following Hume's logical critique of induction, but the novelty of Duhem's work was his proposal that Newton's theory of universal mutual gravity flatly contradicted Kepler's Laws of planetary motion because the interplanetary mutual gravitational perturbations caused deviations from Keplerian orbits. Since no proposition can be validly logically deduced from any it contradicts, according to Duhem, Newton must not have logically deduced his law of gravitation directly from Kepler's Laws. Duhem's name is given to the underdetermination or Duhem–Quine thesis, which holds that for any given set of observations there is an innumerably large number of explanations, it is, in essence, the same as Hume's critique of induction: all three variants point at the fact that empirical evidence cannot force the choice of a theory or its revision.
Possible alternatives to induction are Duhem's instrumentalism and Popper's thesis that we learn from falsification. As popular as the Duhem–Quine thesis may be in the philosophy of science, in reality Pierre Duhem and Willard Van Orman Quine stated different theses. Pierre Duhem believed that experimental theory in physics is fundamentally different from fields like physiology and certain branches of chemistry. Duhem's conception of theoretical group has its limits, since not all concepts are connected to each other logically, he did not include at all a priori disciplines such as logic and mathematics within these theoretical groups in physics which can be tested experimentally. Quine, on the other hand, conceived this theoretical group as a unit of a whole human knowledge. To Quine mathematics and logic must be revised in light of recalcitrant experience, a thesis that Duhem never held. Duhem's philosophy of science was criticized by one of his contemporaries, Abel Rey, in part because of what Rey perceived as influence on the part of Duhem's Cathol
Hans Hahn (mathematician)
Hans Hahn was an Austrian mathematician who made contributions to functional analysis, set theory, the calculus of variations, real analysis, order theory. Born at Vienna as the son of a higher government official of the k.k. Telegraphen-Korrespondenz-Bureau, in 1898 Hahn became a student at the Universität Wien starting with a study of law. In 1899 he switched over to mathematics and spent some time at the universities of Strasbourg, Munich and Göttingen. In 1902 he took his Ph. D. in Vienna, on the subject "Zur Theorie der zweiten Variation einfacher Integrale". He was a student of Gustav von Escherich, he was appointed to the teaching staff in Vienna in 1905. After 1905/1906 as a stand-in for Otto Stolz at Innsbruck and some further years as a Privatdozent in Vienna, he was nominated in 1909 Professor extraordinarius in Czernowitz, at that time a town within the empire of Austria. After joining the Austrian army in 1915, he was badly wounded in 1916 and became again Professor extraordinarius, now in Bonn.
In 1917 he was nominated a regular Professor there and in 1921 he returned to Vienna with this title, where he stayed until his rather early death in 1934 at the age of 54, following cancer surgery. He had married Eleonore Minor in 1909 and they had a daughter, Nora, he was interested in philosophy, was part of a discussion group concerning Mach's positivism with Otto Neurath and Phillip Frank prior to the First World War. In 1922, he helped arrange Moritz Schlick's entry into the group, which led to the founding of the Vienna Circle, the group, at the center of logical positivist thought in the 1920s, his most famous student was Kurt Gödel, whose Ph. D. thesis was completed in 1929. Within the Vienna Circle, Hahn was known for using his mathematical and philosophical work to study psychic phenomena. Hahn's contributions to mathematics include the Hahn–Banach theorem and the uniform boundedness principle. Other theorems include: the Hahn decomposition theorem. Hahn authored the book: according to Arthur Rosenthal, "... formed a great advance in the Theory of Real functions and had a great influence on the further development of this theory".
He was a co-author of the book Set Functions, published in 1948 by Arthur Rosenthal, fourteen years after his death in Vienna in 1934. In 1921 he received the Richard Lieben Prize. In 1926 he was the president of the German Mathematical Society. In 1928 he was an Invited Speaker at the ICM in Bologna. All his mathematical and philosophical works, except all books and all but one of his book reviews, are published in the three volumes, of his "Collected papers". Hahn, Theorie der reellen Funktionen. Erster Band, Berlin–Heidelberg: Springer-Verlag, pp. VII+600, doi:10.1007/978-3-642-52624-4, ISBN 978-3-642-52570-4, JFM 48.0261.09. Hahn, Reelle Funktionen. Tl. 1. Punktfunktionen, Mathematik und ihre Anwendungen in Monographien und Lehrbüchern, Band 13, Leipzig: Akademische Verlagsgesellschaft, pp. XII+415, JFM 58.0242.05, Zbl 0005.38903 Hahn, Hans. Band 1/Vol. 1, Wien: Springer-Verlag, pp. xii+511, ISBN 978-3-211-82682-9, MR 1361405, Zbl 0859.01030 Hahn, Gesammelte Abhandlungen/Collected works. Band 2/Vol.
2, Wien: Springer-Verlag, pp. xiii+545, ISBN 978-3-211-82750-5, MR 1394443, Zbl 0847.01033. Hahn, Gesammelte Abhandlungen/Collected works. Band 3/Vol. 3, Wien: Springer-Verlag, pp. xiii+581, ISBN 978-3-211-82781-9, MR 1452103, Zbl 0881.01046. Domain Mathematical analysis O'Connor, John J.. "Hans Hahn", MacTutor History of Mathematics archive, University of St Andrews. Josef Lense, "Hahn, Mathematiker", Neue Deutsche Biographie, 7, Berlin: Duncker & Humblot, pp. 506–506
A. J. Ayer
Sir Alfred Jules "Freddie" Ayer cited as A. J. Ayer, was an English philosopher known for his promotion of logical positivism in his books Language and Logic and The Problem of Knowledge, he was educated at Eton College and Oxford University, after which he studied the philosophy of logical positivism at the University of Vienna. From 1933 to 1940 he lectured on philosophy at Oxford. During the Second World War Ayer was a Special Operations Executive and MI6 agent, he was Grote Professor of the Philosophy of Mind and Logic at University College London from 1946 until 1959, after which he returned to Oxford to become Wykeham Professor of Logic at New College. He was president of the Aristotelian Society from 1951 to 1952 and knighted in 1970, he was known for his advocacy of humanism, was the second President of the British Humanist Association. Ayer was born in St John's Wood, in north west London, to a wealthy family from continental Europe, his mother, Reine Citroën, was from the Dutch-Jewish family who founded the Citroën car company in France.
His father, Jules Ayer, was a Swiss Calvinist financier. Ayer was educated at Ascham St Vincent's School, a former boarding preparatory school for boys in the seaside town of Eastbourne in Sussex, in which he started boarding at the comparatively early age of seven for reasons to do with the First World War, Eton College, a boarding school in Eton in Berkshire, it was at Eton that Ayer first became known for his characteristic precocity. Although interested in furthering his intellectual pursuits, he was keen on sports rugby, reputedly played the Eton Wall Game well. In the final examinations at Eton, Ayer came second in his year, first in classics. In his final year, as a member of Eton's senior council, he unsuccessfully campaigned for the abolition of corporal punishment at the school, he won a classics scholarship to Oxford. After graduation from Oxford University Ayer spent a year in Vienna, returned to England and published his first book, Language and Logic in 1936; the first exposition in English of Logical Positivism as newly developed by the Vienna Circle, this made Ayer at age 26 the'enfant terrible' of British philosophy.
In the Second World War he served as an officer in the Welsh Guards, chiefly in intelligence. Ayer was commissioned second lieutenant into the Welsh Guards from Officer Cadet Training Unit on 21 September 1940. After the war he returned to Oxford University where he became a fellow and Dean of Wadham College, he thereafter taught philosophy at London University from 1946 until 1959, when he started to appear on radio and television. He was an extrovert and social mixer who liked dancing and attending the clubs in London and New York, he was obsessed with sport: he had played rugby for Eton, was a noted cricketer and a keen supporter of Tottenham Hotspur football team, where he was for many years a season ticket holder. For an academic, Ayer was an unusually well-connected figure in his time, with close links to'high society' and the establishment. Presiding over Oxford high-tables, he is described as charming, but at times he could be intimidating. Ayer was married four times to three women, his first marriage was from 1932–1941 to Renée, who subsequently married philosopher Stuart Hampshire, Ayer's friend and colleague.
In 1960 he married Alberta Constance Wells. Ayer's marriage to Wells was dissolved in 1983 and that same year he married Vanessa Salmon, former wife of politician Nigel Lawson, she died in 1985 and in 1989 he remarried Dee Wells, who survived him. Ayer had a daughter with Hollywood columnist Sheilah Graham Westbrook. From 1959 to his retirement in 1978, Sir Alfred held the Wykeham Chair, Professor of Logic at Oxford, he was knighted in 1970. After his retirement, Ayer taught or lectured several times in the United States, including serving as a visiting professor at Bard College in the fall of 1987. At a party that same year held by fashion designer Fernando Sanchez, Ayer 77, confronted Mike Tyson, forcing himself upon the little-known model Naomi Campbell; when Ayer demanded that Tyson stop, the boxer asked, "Do you know who the fuck I am? I'm the heavyweight champion of the world," to which Ayer replied, "And I am the former Wykeham Professor of Logic. We are both pre-eminent in our field. I suggest that we talk about this like rational men".
Ayer and Tyson began to talk, allowing Campbell to slip out. In 1988, one year before his death, Ayer wrote an article entitled, "What I saw when I was dead", describing an unusual near-death experience. Of the experience, Ayer first said that it "slightly weakened my conviction that my genuine death... will be the end of me, though I continue to hope that it will be." However, a few days he revised this, saying "what I should have said is that my experiences have weakened, not my belief that there is no life after death, but my inflexible attitude towards that belief". Ayer died on 27 June 1989. From 1980 to 1989, Ayer lived at 51 York Street, where a memorial plaque was unveiled on 19 November 1995. In Language and Logic, Ayer presents the verification principle as the only valid basis for philosophy. Unless logical or empirical verification is possible, statements like "God exists" or "charity is good" are not true or untrue but meaningless, may thus be excluded or ignored. Religious language in particular was unverifiable and as such nonsense.
He criticises C. A. Mace's opini
Otto Neurath was an Austrian philosopher, philosopher of science and political economist. Before he fled his native country in 1934, Neurath was one of the leading figures of the Vienna Circle. Neurath was born in Vienna, the son of Wilhelm Neurath, a well-known political economist at the time. Helene Migerka was his cousin, he studied mathematics in Vienna and gained his Ph. D. in the department of Political Science and Statistics at the University of Berlin. He married Anna Schapire in 1907, who died in 1911 while bearing their son and married a close friend, the mathematician and philosopher Olga Hahn; because of his first wife's blindness and because of the outbreak of war, Paul was sent to a children's home outside Vienna, where Neurath's mother lived, returned to live with both of his parents when he was nine years old. Neurath taught political economy at the Neue Wiener Handelsakademie. Subsequently, he directed the Department of War Economy in the War Ministry. In 1917 or 1918, he became director of the Deutsches Kriegswirtschaftsmuseum at Leipzig.
Here he worked with Wolfgang Schumann, known from the Dürerbund for which Neurath had written many articles. During the political crisis which led to the armistice, Schumann urged him to work out a plan for socialization in Saxony. Along with Schumann and Hermann Kranold developed the Programm Kranold-Neurath-Schumann. Neurath joined the German Social Democratic Party in 1918-19 and ran an office for central economic planning in Munich; when the Bavarian Soviet Republic was defeated, Neurath was imprisoned but returned to Austria after intervention from the Austrian government. While in prison he wrote "Anti-Spengler", a critical attack on Oswald Spengler's "Decline of the West". In Red Vienna, he joined the Social Democrats and became secretary of the Austrian Association for Settlements and Small Gardens, a collection of self-help groups that set out to provide housing and garden plots to its members. In 1923, he founded a new museum for city planning called Siedlungsmuseum. In 1925 he renamed it Gesellschafts- und Wirtschaftsmuseum in Wien and founded an own association for it, in which the Vienna city administration, the trade unions, the Chamber of Workers and the Bank of Workers became members mayor Karl Seitz having acted as first proponent of the association.
Julius Tandler, city councillor for welfare and health, served at the first board of the museum together with other prominent social democratic politicians. The museum was provided with exhibition rooms at buildings of the city administration, the most prominent being the People's Hall at the Vienna City Hall. To make the museum understandable for everybody, Neurath worked on graphic design and visual education. In the late 1920s, graphic designer and communications theorist Rudolf Modley served as an assistant to Neurath, contributing to a new means of communication: a visual "language." With the illustrator Gerd Arntz and with Marie Reidemeister, Neurath created Isotype, a symbolic way of representing quantitative information via interpretable icons. At international conventions of city planners, Neurath presented and promoted his communication tools. In the 1920s, Neurath became an ardent logical positivist, was the main author of the Vienna Circle manifesto, he was the driving force behind the Unity of Science movement and the International Encyclopedia of Unified Science.
During the 1930s, he began promoting Isotype as an International Picture Language, connecting it both with the adult education movement and with the Internationalist passion for new and artificial languages, although he stressed in talks and correspondence that Isotype was not intended to be a stand-alone language, was limited in what it could communicate. During the Austrian Civil War in 1934, Neurath had been working in Moscow. Anticipating problems, he had asked to get a coded message in case it would be dangerous for him to return to Austria; as Marie Reidemeister reported after receiving the telegram "Carnap is waiting for you," Neurath chose to travel to The Hague, the Netherlands, instead of Vienna, to be able to continue his international work. He was joined by Arntz, his wife fled to the Netherlands, where she died in 1937. After the Luftwaffe had bombed Rotterdam, he and Marie Reidemeister fled to England, crossing the Channel with other refugees in an open boat, he and Reidemeister married in 1941 after a period of being interned on the Isle of Man.
In England, he and his wife set up the Isotype Institute in Oxford and he was asked to advise on, design Isotype charts for, the intended redevelopment of the slums of Bilston, near Wolverhampton. Neurath died and unexpectedly, in December 1945. After his death, Marie Neurath continued the work of the Isotype Institute, publishing Neurath's writings posthumously, completing projects he had started and writing many children's books using the Isotype system, until her death in the 1980s. Most work by and about Neurath is still available only in German; however he wrote in English, using Ogden's Basic English. His scientific papers are held at the Noord-Hollands Archief in Haarlem. Neurath's work on protocol sentences tried to reconcile an empiricist concern for the grounding of knowl
Aesthetics is a branch of philosophy that deals with the nature of art and taste and with the creation or appreciation of beauty. In its more technical epistemological perspective, it is defined as the study of subjective and sensori-emotional values, or sometimes called judgments of sentiment and taste. Aesthetics studies how artists imagine and perform works of art, it studies how they feel about art—why they like some works and not others, how art can affect their moods and attitude toward life. The phrase was coined in English in the 18th century. More broadly, scholars in the field define aesthetics as "critical reflection on art and nature". In modern English, the term aesthetic can refer to a set of principles underlying the works of a particular art movement or theory: one speaks, for example, of the Cubist aesthetic; the word aesthetic is derived from the Greek αἰσθητικός, which in turn was derived from αἰσθάνομαι (aisthanomai, meaning "I perceive, sense" and related to αἴσθησις. Aesthetics in this central sense has been said to start with the series of articles on “The Pleasures of the Imagination” which the journalist Joseph Addison wrote in the early issues of the magazine The Spectator in 1712.
The term "aesthetics" was appropriated and coined with new meaning by the German philosopher Alexander Baumgarten in his dissertation Meditationes philosophicae de nonnullis ad poema pertinentibus in 1735. Aesthetics, a not tidy intellectual discipline, is a heterogeneous collection of problems that concern the arts but relate to nature. Even though his definition in the fragment Aesthetica is more referred to as the first definition of modern aesthetics. Aesthetics is for the artist; some separate aesthetics and philosophy of art, claiming that the former is the study of beauty while the latter is the study of works of art. However, most Aesthetics encompasses both questions around beauty as well as questions about art, it examines topics such as aesthetic objects, aesthetic experience, aesthetic judgments. For some, aesthetics is considered a synonym for the philosophy of art since Hegel, while others insist that there is a significant distinction between these related fields. In practice, aesthetic judgement refers to the sensory contemplation or appreciation of an object, while artistic judgement refers to the recognition, appreciation or criticism of art or an art work.
Philosophical aesthetics has not only to speak about art and to produce judgments about art works, but has to give a definition of what art is. Art is an autonomous entity for philosophy, because art deals with the senses and art is as such free of any moral or political purpose. Hence, there are two different conceptions of art in aesthetics: art as knowledge or art as action, but aesthetics is neither epistemology nor ethics. Aestheticians compare historical developments with theoretical approaches to the arts of many periods, they study the varieties of art in relation to their physical and culture environments. Aestheticians use psychology to understand how people see, imagine, think and act in relation to the materials and problems of art. Aesthetic psychology studies the creative process and the aesthetic experience. Aesthetics examines our affective domain response to an object or phenomenon Judgments of aesthetic value rely on our ability to discriminate at a sensory level. However, aesthetic judgments go beyond sensory discrimination.
For David Hume, delicacy of taste is not "the ability to detect all the ingredients in a composition", but our sensitivity "to pains as well as pleasures, which escape the rest of mankind." Thus, the sensory discrimination is linked to capacity for pleasure. For Immanuel Kant, "enjoyment" is the result when pleasure arises from sensation, but judging something to be "beautiful" has a third requirement: sensation must give rise to pleasure by engaging our capacities of reflective contemplation. Judgments of beauty are sensory and intellectual all at once. Kant observed of a man "If he says that canary wine is agreeable he is quite content if someone else corrects his terms and reminds him to say instead: It is agreeable to me," because "Everyone has his own taste"; the case of "beauty" is different from mere "agreeableness" because, "If he proclaims something to be beautiful he requires the same liking from others. Roger Scruton has argued similarly. Viewer interpretations of beauty may on occasion be observed to possess two concepts of value: aesthetics and taste.
Aesthetics is the philosophical notion of beauty. Taste is a result of an education process and awareness of elite cultural values learned through exposure to mass culture. Bourdieu examined how the elite in society define the aesthetic values like taste and how varying levels of exposure to these values can result in variations by class, cultural background, education. According to Kant, beauty is universal. In the opinion of Władysław Tatarkiewicz, there are
A statement, hypothesis, or theory has falsifiability if it is contradicted by a basic statement, which, in an eventual successful or failed falsification, must correspond to a true or hypothetical observation. For example, the claim "all swans are white and have always been white" is falsifiable since it is contradicted by this basic statement: "In 1697, during the Dutch explorer Willem de Vlamingh expedition, there were black swans on the shore of the Swan River in Australia", which in this case is a true observation; the concept is known by the terms refutable and refutability. The concept was introduced by the philosopher of science Karl Popper, he saw falsifiability as the logical part and the cornerstone of his scientific epistemology, which sets the limits of scientific inquiry. He proposed that theories that are not falsifiable are unscientific. Declaring an unfalsifiable theory to be scientific would be pseudoscience; the classical view of the philosophy of science is that it is the goal of science to prove hypotheses like "All swans are white" or to induce them from observational data.
The Inductivist methodology supposes that one can somehow move from a series of statements such as'here is a white swan','over there is a white swan', so on, to a universal statement such as'all swans are white'. As observed by David Hume, Immanuel Kant and by Popper and others, this method is deductively invalid, since it is always possible that there may be a non-white swan that has eluded observation; this is known as the problem of induction. One solution to the problem of induction, proposed by Immanuel Kant in Critique of Pure Reason, is to consider as valid a priori, the conclusions that we would otherwise have drawn from these dubious inferential inductions. Following Kant, Popper accepted that we have to work with unproven hypotheses, but he refused that we have to justify them in any way and he wrote: "I do not think that his ingenious attempt to provide an a priori justification for synthetic statements was successful." However, if one finds one single swan, not white, deductive logic admits the conclusion that the statement that all swans are white is false.
Falsificationism thus strives for questioning, for falsification, of hypotheses instead of proving them or trying to view them as valid in any way. For a statement to be questioned using observation, it needs to be at least theoretically possible that it can come into conflict with observation. A key observation of falsificationism is thus that a criterion of demarcation is needed to distinguish those statements that can come into conflict with observation and those that cannot, but the criterion itself concerns only the logical form of the theory: I shall require that logical form shall be such that it can be singled out, by means of empirical tests, in a negative sense: it must be possible for an empirical scientific system to be refuted by experience. Popper always insisted on a clear distinction between the logic and its applied less precise methodology; the required logical form, the criterion, is that there must exist basic statements that contradict the theory. This logical form informally implies the possibility of refutations by experience because, in its informal methodological context, a basic statement must be intersubjective and interpretable in terms of observations.
Objections can be raised against falsifiability as a criterion of demarcation similar to those which can be raised against verifiability. For example, as pointed out by many and reformulated by Colin McGinn, e have to be able to infer that if a falsifying result has been found in a given experiment it will be found in future experiments. Early, in anticipation of this specific objection Popper wrote, This attack would not disturb me. My proposal is based upon an asymmetry between falsifiability. For these are never derivable from singular statements, but can be contradicted by singular statements. In its simple form, the point here is that although a singular existential statement such as'there is a white swan in Europe' cannot be used to affirm a universal statement, it can be used to show that one is false: the statement'there is a non white swan in Australia' implies that the universal statement'all swans are white' is false. Moreover, this singular existential statement is empirical: it is impractical to observe all the swans in the world to verify that they are all white, but one can observe one swan, not white.
This shows the fundamental difference between falsifiability. In the logical form of the theory, there is no notion of future experiments, but only a class of basic statements that contradict it; such a simple contradiction with a basic statement is not. A falsification entails a derivation from a system of statements, which include the universal statement and initial conditions, to a singular statement, contradicted by a falsifying hypothesis, but the argument can be generalized. Popper explains "... it is possible by means of purely deductive inferences to argue from the truth of singular statements to the falsity of universal statements. Such an argument to the falsity of universal statements is the only deductive kind of inference that proceeds, as it were, in the ‘inducti