William Stanley Jevons
William Stanley Jevons
1 September 1835
|Died||13 August 1882 46) (aged|
|Alma mater||University College London|
|Known for|| Marginal utility theory |
|Fields|| Economics |
|Institutions|| University College London (1876–80)|
Owens College (now University of Manchester) (1863–75)
|Academic advisors||Augustus De Morgan|
|Influenced|| Frank Fetter |
William Stanley Jevons FRS ( // ; 1 September 1835 –13 August 1882) was an English economist and logician.
Fellowship of the Royal Society is an award granted to individuals that the Royal Society of London judges to have made a 'substantial contribution to the improvement of natural knowledge, including mathematics, engineering science, and medical science'.
An economist is a practitioner in the social science discipline of economics.
Logic is the systematic study of the form of valid inference, and the most general laws of truth. A valid inference is one where there is a specific relation of logical support between the assumptions of the inference and its conclusion. In ordinary discourse, inferences may be signified by words such as therefore, thus, hence, ergo, and so on.
Irving Fisher described Jevons's book A General Mathematical Theory of Political Economy (1862) as the start of the mathematical method in economics.It made the case that economics as a science concerned with quantities is necessarily mathematical. In so doing, it expounded upon the "final" (marginal) utility theory of value. Jevons' work, along with similar discoveries made by Carl Menger in Vienna (1871) and by Léon Walras in Switzerland (1874), marked the opening of a new period in the history of economic thought. Jevons's contribution to the marginal revolution in economics in the late 19th century established his reputation as a leading political economist and logician of the time.
Irving Fisher was an American economist, statistician, inventor, and Progressive social campaigner. He was one of the earliest American neoclassical economists, though his later work on debt deflation has been embraced by the post-Keynesian school. Joseph Schumpeter described him as "the greatest economist the United States has ever produced", an assessment later repeated by James Tobin and Milton Friedman.
In economics, nominal value is measured in terms of money, whereas real value is measured against goods or services. A real value is one which has been adjusted for inflation, enabling comparison of quantities as if the prices of goods had not changed on average. Changes in value in real terms therefore exclude the effect of inflation. In contrast with a real value, a nominal value has not been adjusted for inflation, and so changes in nominal value reflect at least in part the effect of inflation.
Carl Menger was an Austrian economist and the founder of the Austrian School of economics. Menger contributed to the development of the theory of marginalism, which rejected the cost-of-production theories of value, such as were developed by the classical economists such as Adam Smith and David Ricardo. As a departure from such, he would go on to call his resultant perspective, the “Subjective Theory of Value”.
Jevons broke off his studies of the natural sciences in London in 1854 to work as an assayer in Sydney, where he acquired an interest in political economy. Returning to the UK in 1859, he published General Mathematical Theory of Political Economy in 1862, outlining the marginal utility theory of value, and A Serious Fall in the Value of Gold in 1863. For Jevons, the utility or value to a consumer of an additional unit of a product is inversely related to the number of units of that product he already owns, at least beyond some critical quantity.
A metallurgical assay is a compositional analysis of an ore, metal, or alloy.
Sydney is the state capital of New South Wales and the most populous city in Australia and Oceania. Located on Australia's east coast, the metropolis surrounds Port Jackson and extends about 70 km (43.5 mi) on its periphery towards the Blue Mountains to the west, Hawkesbury to the north, the Royal National Park to the south and Macarthur to the south-west. Sydney is made up of 658 suburbs, 40 local government areas and 15 contiguous regions. Residents of the city are known as "Sydneysiders". As of June 2017, Sydney's estimated metropolitan population was 5,230,330 and is home to approximately 65% of the state's population.
Political economy is the study of production and trade and their relations with law, custom and government; and with the distribution of national income and wealth. As a discipline, political economy originated in moral philosophy, in the 18th century, to explore the administration of states' wealth, with "political" signifying the Greek word polity and "economy" signifying the Greek word "okonomie". The earliest works of political economy are usually attributed to the British scholars Adam Smith, Thomas Malthus, and David Ricardo, although they were preceded by the work of the French physiocrats, such as François Quesnay (1694–1774) and Anne-Robert-Jacques Turgot (1727–1781).
Jevons received public recognition for his work on The Coal Question (1865), in which he called attention to the gradual exhaustion of Britain's coal supplies and also put forth the view that increases in energy production efficiency leads to more, not less, consumption. 7f, 161f This view is known today as the Jevons paradox, named after him. Due to this particular work, Jevons is regarded today as the first economist of some standing to develop an 'ecological' perspective on the economy. :295f :147 :2:
The Coal Question; An Inquiry Concerning the Progress of the Nation, and the Probable Exhaustion of Our Coal Mines is a book that economist William Stanley Jevons wrote in 1865 to explore the implications of Britain's reliance on coal. Given that coal was a finite, non-renewable energy resource, Jevons raised the question of sustainability. "Are we wise," he asked rhetorically, "in allowing the commerce of this country to rise beyond the point at which we can long maintain it?" His central thesis was that the supremacy of the United Kingdom of Great Britain and Ireland over global affairs was transitory, given the finite nature of its primary energy resource. In propounding this thesis, Jevons covered a range of issues central to sustainability, including limits to growth, overpopulation, overshoot, energy return on energy input (EROEI), taxation of energy resources, renewable energy alternatives, and resource peaking—a subject widely discussed today under the rubric of peak oil.
Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other elements; chiefly hydrogen, sulfur, oxygen, and nitrogen. Coal is formed when dead plant matter decays into peat and is converted into coal by the heat and pressure of deep burial over millions of years. Vast deposits of coal originates in former wetlands—called coal forests—that covered much of the Earth's tropical land areas during the late Carboniferous (Pennsylvanian) and Permian times.
In economics, the Jevons paradox occurs when technological progress or government policy increases the efficiency with which a resource is used, but the rate of consumption of that resource rises due to increasing demand. The Jevons paradox is perhaps the most widely known paradox in environmental economics. However, governments and environmentalists generally assume that efficiency gains will lower resource consumption, ignoring the possibility of the paradox arising.
The most important of his works on logic and scientific methods is his Principles of Science (1874),as well as The Theory of Political Economy (1871) and The State in Relation to Labour (1882). Among his inventions was the logic piano, a mechanical computer.
The scientific method is an empirical method of acquiring knowledge that has characterized the development of science since at least the 17th century. It involves careful observation, applying rigorous skepticism about what is observed, given that cognitive assumptions can distort how one interprets the observation. It involves formulating hypotheses, via induction, based on such observations; experimental and measurement-based testing of deductions drawn from the hypotheses; and refinement of the hypotheses based on the experimental findings. These are principles of the scientific method, as distinguished from a definitive series of steps applicable to all scientific enterprises.
A computer is a machine that can be instructed to carry out sequences of arithmetic or logical operations automatically via computer programming. Modern computers have the ability to follow generalized sets of operations, called programs. These programs enable computers to perform an extremely wide range of tasks. A "complete" computer including the hardware, the operating system, and peripheral equipment required and used for "full" operation can be referred to as a computer system. This term may as well be used for a group of computers that are connected and work together, in particular a computer network or computer cluster.
Jevons was born in Liverpool, Lancashire, England. His father, Thomas Jevons, was an iron merchant who wrote about legal and economic subjects as well. His mother Mary Anne Jevons was the daughter of William Roscoe. At the age of fifteen he was sent to London to attend the University College School. Around this time, he seemed to have formed the belief that he was capable of important achievements as a thinker. Towards the end of 1853, after having spent two years at University College, where his favourite subjects were chemistry and botany, he received an offer as metallurgical assayer for the new mint in Australia. The idea of leaving the UK was distasteful, but pecuniary considerations had, in consequence of the failure of his father's firm in 1847, become of vital importance, and he accepted the post.
Liverpool is a city and metropolitan borough in Merseyside, England. As of 2018, the population of Liverpool is approximately 494,814. Liverpool is the ninth-largest English district by population, and the largest in Merseyside and the Liverpool City Region. It lies within the United Kingdom's sixth-most populous urban area, and at the centre of the fifth-largest metropolitan area with a population of 2.24 million.
Lancashire is a ceremonial county in North West England. The administrative centre is Preston. The county has a population of 1,449,300 and an area of 1,189 square miles (3,080 km2). People from Lancashire are known as Lancastrians.
Mary Anne Jevons, néeRoscoe (1795–1845) was an English poet.
Jevons left the UK for Sydney in June 1854 to take up a role as an Assayer at the Mint. Jevons lived with his colleague and his wife first at Church Hill, then in Annangrove at Petersham and at Double Bay before returning to England. In letters to his family he described his life, took photographs and produced a social map of Sydney. Jevons returned to England via America five years later.
He resigned his appointment, and in the autumn of 1859 re-entered the University College London as a student. He was granted B.A. and M.A. degrees from the University of London. He now gave his principal attention to the moral sciences, but his interest in natural science was by no means exhausted: throughout his life he continued to write occasional papers on scientific subjects, and his knowledge of the physical sciences greatly contributed to the success of his chief logical work, The Principles of Science. Not long after taking his M.A. degree, Jevons obtained a post as tutor at Owens College, Manchester.
In 1866, he was elected professor of logic and mental and moral philosophy and Cobden professor of political economy at Owens College.
Jevons arrived quite early in his career at the doctrines that constituted his most characteristic and original contributions to economics and logic. The theory of utility, which became the keynote of his general theory of political economy, was practically formulated in a letter written in 1860; and the germ of his logical principles of the substitution of similars may be found in the view which he propounded in another letter written in 1861, that "philosophy would be found to consist solely in pointing out the likeness of things." The theory of utility above referred to, namely, that the degree of utility of a commodity is some continuous mathematical function of the quantity of the commodity available, together with the implied doctrine that economics is essentially a mathematical science, took more definite form in a paper on "A General Mathematical Theory of Political Economy", written for the British Association in 1862. This paper does not appear to have attracted much attention either in 1862 or on its publication four years later in the Journal of the Statistical Society; and it was not till 1871, when the Theory of Political Economy appeared, that Jevons set forth his doctrines in a fully developed form.
It was not until after the publication of this work that Jevons became acquainted with the applications of mathematics to political economy made by earlier writers, notably Antoine Augustin Cournot and H.H. Gossen. The theory of utility was at about 1870 being independently developed on somewhat similar lines by Carl Menger in Austria and Léon Walras in Switzerland. As regards the discovery of the connection between value in exchange and final (or marginal) utility, the priority belongs to Gossen, but this in no way detracts from the great importance of the service which Jevons rendered to British economics by his fresh discovery of the principle, and by the way in which he ultimately forced it into notice. In his reaction from the prevailing view he sometimes expressed himself without due qualification: the declaration, for instance, made at the commencement of the Theory of Political Economy, that value depends entirely upon utility, lent itself to misinterpretation. But a certain exaggeration of emphasis may be pardoned in a writer seeking to attract the attention of an indifferent public. The Neoclassical Revolution, which would reshape economics, had been started.
Jevons did not explicitly distinguish between the concepts of ordinal and cardinal utility. Cardinal utility allows the relative magnitude of utilities to be discussed, while ordinal utility only implies that goods can be compared and ranked according to which good provided the most utility. Although Jevons predated the debate about ordinality or cardinality of utility, his mathematics required the use of cardinal utility functions. For example, in "The Theory of Political Economy", Chapter II, the subsection on "Theory of Dimensions of Economic Quantities", Jevons makes the statement that "In the first place, pleasure and pain must be regarded as measured upon the same scale, and as having, therefore, the same dimensions, being quantities of the same kind, which can be added and subtracted...." Speaking of measurement, addition and subtraction requires cardinality, as does Jevons's heavy use of integral calculus. Note that cardinality does not imply direct measurability, in which Jevons did not believe.
It was not, however, as a theorist dealing with the fundamental data of economic science, but as a writer on practical economic questions, that Jevons first received general recognition. A Serious Fall in the Value of Gold (1863) and The Coal Question (1865) placed him in the front rank as a writer on applied economics and statistics; and he would be remembered as one of the leading economists of the 19th century even had his Theory of Political Economy never been written. His economic works include Money and the Mechanism of Exchange (1875) written in a popular style, and descriptive rather than theoretical; a Primer on Political Economy (1878); The State in Relation to Labour (1882), and two works published after his death, Methods of Social Reform" and "Investigations in Currency and Finance, containing papers that had appeared separately during his lifetime. The last-named volume contains Jevons's speculations on the connection between commercial crises and sunspots. He was engaged at the time of his death upon the preparation of a large treatise on economics and had drawn up a table of contents and completed some chapters and parts of chapters. This fragment was published in 1905 under the title of The Principles of Economics: a fragment of a treatise on the industrial mechanism of society, and other papers.
In The Coal Question, Jevons covered a breadth of concepts on energy depletion that have recently been revisited by writers covering the subject of peak oil. For example, Jevons explained that improving energy efficiency typically reduced energy costs and thereby increased rather than decreased energy use, an effect now known as the Jevons paradox. The Coal Question remains a paradigmatic study of resource depletion theory. Jevons's son, H. Stanley Jevons, published an 800-page follow-up study in 1915 in which the difficulties of estimating recoverable reserves of a theoretically finite resource are discussed in detail.
In 1875, Jevons read a paper On the influence of the sun-spot period upon the price of corn at a meeting of the British Association for the Advancement of Science. This captured the attention of the media and led to the coining of the word sunspottery for claims of links between various cyclic events and sun-spots. In a later work, "Commercial Crises and Sun-Spots",Jevons analyzed business cycles, proposing that crises in the economy might not be random events, but might be based on discernible prior causes. To clarify the concept, he presented a statistical study relating business cycles with sunspots. His reasoning was that sunspots affected the weather, which, in turn, affected crops. Crop changes could then be expected to cause economic changes. Subsequent studies have found that sunny weather has a small but significant positive impact on stock returns, probably due to its impact on traders' moods.
In 1864 Jevons published a Pure Logic; or, the Logic of Quality apart from Quantity, which was based on Boole's system of logic, but freed from what he considered the false mathematical dress of that system. In the years immediately following he devoted considerable attention to the construction of a logical machine, exhibited before the Royal Society in 1870, by means of which [ clarification needed ] could be mechanically obtained. In 1866 what he regarded as the great and universal principle of all reasoning dawned upon him; and in 1869 he published a sketch of this fundamental doctrine under the title of The Substitution of Similars . He expressed the principle in its simplest form as follows: "Whatever is true of a thing is true of its like", and he worked out in detail its various applications including the logical abacus (a cross between logical abacus and a piano – "Logic Piano"), a mechanical computer he designed and had built in 1866.
In the following year appeared the Elementary Lessons on Logic, which soon became the most widely read elementary textbook on logic in the English language. In the meantime he was engaged upon a much more important logical treatise, which appeared in 1874 under the title of The Principles of Science. In this work Jevons embodied the substance of his earlier works on pure logic and the substitution of similars; he also enunciated and developed the view that induction is simply an inverse employment of deduction; he treated in a luminous manner the general theory of probability, and the relation between probability and induction; and his knowledge of the various natural sciences enabled him throughout to relieve the abstract character of logical doctrine by concrete scientific illustrations, often worked out in great detail. An example is his discussion of the use of one-way functions in cryptography, including remarks on the integer factorization problem that foreshadowed its use in public-key cryptography. Jevons's general theory of induction was a revival of the theory laid down by Whewell and criticised by John Stuart Mill; but it was put in a new form, and was free from some of the non-essential adjuncts which rendered Whewell's exposition open to attack. The work as a whole was one of the most notable contributions to logical doctrine that appeared in the UK in the 19th century. "Though less attractively written than Mill's System of Logic, Principles of Science is a book that keeps much closer to the facts of scientific practice."His Studies in Deductive Logic, consisting mainly of exercises and problems for the use of students, was published in 1880. In 1877 and the following years Jevons contributed to the Contemporary Review some articles on Mill, which he had intended to supplement by further articles, and eventually publish in a volume as a criticism of Mill's philosophy. These articles and one other were republished after Jevons's death, together with his earlier logical treatises, in a volume, entitled Pure Logic, and other Minor Works. The criticisms on Mill contain much that is ingenious and much that is forcible, but on the whole they cannot be regarded as taking rank with Jevons's other work. His strength lay in his power as an original thinker rather than as a critic; and he will be remembered by his constructive work as logician, economist and statistician.
On Jevons as logician, see Grattan-Guinness (2000).
Jevons wrote in his Principles of Science: "Can the reader say what two numbers multiplied together will produce the number 8,616,460,799? I think it unlikely that anyone but myself will ever know."This became known as Jevons's number and was factored by Charles J. Busk in 1889 , Derrick Norman Lehmer in 1903, and later on a pocket calculator by Solomon W. Golomb. It is the product of two prime numbers, 89,681 and 96,079.
One of Jevons's contemporaries, Hermann von Helmholtz, who was interested in non-Euclidean geometry,discussed two groups of two-dimensional creatures with one group living in the plane while the other living in the surface of a sphere. He asserted that since these creatures were embedded in two dimensions, they would develop a planar version of Euclidean geometry, but that since the nature of these surfaces were different, they would arrive at very different versions of this geometry. He then extended this argument into three dimensions, noting that this raises fundamental questions of the relationship of spatial perception to mathematical truth.
Jevons made an almost immediate response to this article. While Helmholtz focused on how humans perceived space, Jevons focused on the question of truth in geometry. Jevons agreed that while Helmholtz's argument was compelling in constructing a situation where the Euclidean axioms of geometry would not apply, he believed that they had no effect on the truth of these axioms. Jevons hence makes the distinction between truth and applicability or perception, suggesting that these concepts were independent in the domain of geometry.
Jevons did not claim that geometry was developed without any consideration for spatial reality. Instead, he suggested that his geometric systems were representations of reality but in a more fundamental way that transcends what one can perceive about reality.Jevons claimed that there was a flaw in Helmholtz's argument relating to the concept of infinitesimally small. This concept involves how these creatures reason about geometry and space at a very small scale, which is not necessarily the same as the reasoning that Helmholtz assumed on a more global scale. Jevons claimed that the Euclidean relations could be reduced locally in the different scenarios that Helmholtz created and hence the creatures should have been able to experience the Euclidean properties, just in a different representation. For example, Jevons claimed that the two-dimensional creatures living on the surface of a sphere should be able to construct the plane and even construct systems of higher dimensions and that although they may not be able to perceive such situations in reality, it would reveal fundamental mathematical truths in their theoretical existence.
In 1872, Helmholtz gave a response to Jevons, who claimed that Helmholtz failed to show why geometric truth should be separate from the reality of spatial perception. Helmholtz criticized Jevons's definition of truth and in particular, experiential truth. Helmholtz asserts that there should be a difference between experiential truth and mathematical truth and that these versions of truth are not necessarily consistent. This conversation between Helmholtz and Jevons was a microcosm of an ongoing debate between truth and perception in the wake of the introduction of non-Euclidean geometry in the late 19th century.
In 1867, Jevons married Harriet Ann Taylor, whose father, John Edward Taylor, had been the founder and proprietor of the Manchester Guardian . Jevons suffered from ill health and sleeplessness, and found the delivery of lectures covering so wide a range of subjects very burdensome. In 1876, he was glad to exchange the Owens professorship for the professorship of political economy in University College, London. Travelling and music were the principal recreations of his life; but his health continued to be bad, and he suffered from depression. He found his professorial duties increasingly irksome, and feeling that the pressure of literary work left him no spare energy, he decided in 1880 to resign the post. On 13 August 1882 he drowned whilst bathing near Hastings.
Jevons was brought up a Christian Unitarian.Excerpts from his journals indicate he remained committed to his Christian beliefs until death. He is buried in the Hampstead Cemetery.
Jevons was a prolific writer, and at the time of his death was a leader in the UK both as a logician and as an economist. Alfred Marshall said of his work in economics that it "will probably be found to have more constructive force than any, save that of Ricardo, that has been done during the last hundred years."
Jevons's theory of induction has continued to be influential: "Jevons's general view of induction has received a powerful and original formulation in the work of a modern-day philosopher, Professor K. R. Popper."
Neoclassical economics is an approach to economics focusing on the determination of goods, outputs, and income distributions in markets through supply and demand. This determination is often mediated through a hypothesized maximization of utility by income-constrained individuals and of profits by firms facing production costs and employing available information and factors of production, in accordance with rational choice theory, a theory that has come under considerable question in recent years.
George Boole was a largely self-taught English mathematician, philosopher and logician, most of whose short career was spent as the first professor of mathematics at Queen's College, Cork in Ireland. He worked in the fields of differential equations and algebraic logic, and is best known as the author of The Laws of Thought (1854) which contains Boolean algebra. Boolean logic is credited with laying the foundations for the information age. Boole maintained that:
No general method for the solution of questions in the theory of probabilities can be established which does not explicitly recognise, not only the special numerical bases of the science, but also those universal laws of thought which are the basis of all reasoning, and which, whatever they may be as to their essence, are at least mathematical as to their form.
Alfred Marshall, FBA was one of the most influential economists of his time. His book, Principles of Economics (1890), was the dominant economic textbook in England for many years. It brings the ideas of supply and demand, marginal utility, and costs of production into a coherent whole. He is known as one of the founders of neoclassical economics. Although Marshall took economics to a more mathematically rigorous level, he did not want mathematics to overshadow economics and thus make economics irrelevant to the layman.
Marie-Esprit-Léon Walras was a French mathematical economist and Georgist. He formulated the marginal theory of value and pioneered the development of general equilibrium theory.
Friedrich Ludwig Gottlob Frege was a German philosopher, logician, and mathematician. He worked as a mathematics professor at the University of Jena, and is understood by many to be the father of analytic philosophy, concentrating on the philosophy of language, logic, and mathematics. Though largely ignored during his lifetime, Giuseppe Peano (1858–1932) and Bertrand Russell (1872–1970) introduced his work to later generations of philosophers.
A logical abacus is a mechanical digital computer.
Alfred Tarski, born Alfred Teitelbaum, was a Polish-American logician and mathematician of Polish-Jewish descent. Educated in Poland at the University of Warsaw, and a member of the Lwów–Warsaw school of logic and the Warsaw school of mathematics, he immigrated to the United States in 1939 where he became a naturalized citizen in 1945. Tarski taught and carried out research in mathematics at the University of California, Berkeley, from 1942 until his death in 1983.
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Frank Plumpton Ramsey was a British philosopher, mathematician, and economist who made major contributions to all three fields before his death at the age of 26. He was a close friend of Ludwig Wittgenstein and was instrumental in translating Wittgenstein's Tractatus Logico-Philosophicus into English, as well as persuading Wittgenstein to return to philosophy and Cambridge. Like Wittgenstein, he was a member of the Cambridge Apostles, the intellectual secret society, from 1921.
Francis Ysidro Edgeworth was an Anglo-Irish philosopher and political economist who made significant contributions to the methods of statistics during the 1880s. From 1891 onward, he was appointed the founding editor of The Economic Journal.
Bastiaan Cornelis van Fraassen is a Dutch-American philosopher noted for his seminal contributions to philosophy of science. He is a Distinguished Professor of Philosophy at San Francisco State University and the McCosh Professor of Philosophy Emeritus at Princeton University.
Hermann Heinrich Gossen was a Prussian economist who is often regarded as the first to elaborate a general theory of marginal utility.
Harald Ludvig Westergaard was a Danish statistician and economist known for his work in demography and the history of statistics.
William Ernest Johnson, usually cited as W. E. Johnson, was a British philosopher, logician and economic theorist. He is mainly remembered for his 3 volume Logic which introduced the concept of exchangeability
Economic methodology is the study of methods, especially the scientific method, in relation to economics, including principles underlying economic reasoning. In contemporary English, 'methodology' may reference theoretical or systematic aspects of a method. Philosophy and economics also takes up methodology at the intersection of the two subjects.
Applied economics is the application of economic theory and econometrics in specific settings. As one of the two sets of fields of economics, it is typically characterized by the application of the core, i.e. economic theory and econometrics, to address practical issues in a range of fields including demographic economics, labour economics, business economics, industrial organization, agricultural economics, development economics, education economics, engineering economics, financial economics, health economics, monetary economics, public economics, and economic history.
Conventionalism is the philosophical attitude that fundamental principles of a certain kind are grounded on agreements in society, rather than on external reality. Unspoken rules play key factor to the philosophies structure. Although this attitude is commonly held with respect to the rules of grammar, its application to the propositions of ethics, law, science, mathematics, and logic is more controversial.
In economics, utility is the satisfaction or benefit derived by consuming a product; thus the marginal utility of a goods or service is the change in the utility from an increase in the consumption of that good or service.
Various definitions of 'economics' have been proposed, including the definition of 'economics' as "what economists do".
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