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Thursday, June 1, 2023

Circumnavigation

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Circumnavigation
 
The Magellan-Elcano expedition was the first recorded circumnavigation of the Earth.

Circumnavigation is the complete navigation around an entire island, continent, or astronomical body (e.g. a planet or moon). This article focuses on the circumnavigation of Earth.

The first circumnavigation of the Earth was the Magellan Expedition, which sailed from Sanlucar de Barrameda, Spain in 1519 and returned in 1522, after crossing the Atlantic, Pacific, and Indian oceans. Since the rise of commercial aviation in the late 20th century, circumnavigating Earth is straightforward, usually taking days instead of years. Today, the challenge of circumnavigating Earth has shifted towards human and technological endurance, speed, and less conventional methods.

Etymology

The word circumnavigation is a noun formed from the verb circumnavigate, from the past participle of the Latin verb circumnavigare, from circum "around" + navigare "to sail" (see further Navigation § Etymology).

Definition

A person walking completely around either pole will cross all meridians, but this is not generally considered a "circumnavigation". The path of a true (global) circumnavigation forms a continuous loop on the surface of Earth separating two regions of comparable area. A basic definition of a global circumnavigation would be a route which covers roughly a great circle, and in particular one which passes through at least one pair of points antipodal to each other. In practice, people use different definitions of world circumnavigation to accommodate practical constraints, depending on the method of travel. Since the planet is quasispheroidal, a trip from one Pole to the other, and back again on the other side, would technically be a circumnavigation. There are practical difficulties (namely, the Arctic ice pack and the Antarctic ice sheet) in such a voyage, although it was successfully undertaken in the early 1980s by Ranulph Fiennes.

History

The first circumnavigation was that of the ship Victoria between 1519 and 1522, now known as the Magellan–Elcano expedition. It was a Castilian (Spanish) voyage of discovery. The voyage started in Seville, crossed the Atlantic Ocean, and—after several stops—rounded the southern tip of South America, where the expedition named the Strait of Magellan. It then continued across the Pacific, discovering a number of islands on its way (including Guam), before arriving in the Philippines. The voyage was initially led by the Portuguese Ferdinand Magellan but he was killed on Mactan in the Philippines in 1521. The remaining sailors decided to circumnavigate the world instead of making the return voyage—no passage east across the Pacific would be successful for four decades—and continued the voyage across the Indian Ocean, round the southern cape of Africa, north along Africa's Atlantic coasts, and back to Spain in 1522. Only 18 men were still with the expedition at the end, including its surviving captain, the Spaniard Juan Sebastián Elcano.

The next to circumnavigate the globe were the survivors of the Castilian/Spanish expedition of García Jofre de Loaísa between 1525 and 1536. None of the seven original ships of the Loaísa expedition nor its first four leaders—Loaísa, Elcano, Salazar, and Íñiguez—survived to complete the voyage. The last of the original ships, the Santa María de la Victoria, was sunk in 1526 in the East Indies (now Indonesia) by the Portuguese. Unable to press forward or retreat, Hernando de la Torre erected a fort on Tidore, received reinforcements under Alvaro de Saavedra that were similarly defeated, and finally surrendered to the Portuguese. In this way, a handful of survivors became the second group of circumnavigators when they were transported under guard to Lisbon in 1536. A third group came from the 117 survivors of the similarly failed Villalobos Expedition in the next decade; similarly ruined and starved, they were imprisoned by the Portuguese and transported back to Lisbon in 1546.

In 1577, Elizabeth I sent Francis Drake to start an expedition against the Spanish along the Pacific coast of the Americas. Drake set out from Plymouth, England in November 1577, aboard Pelican, which he renamed Golden Hind mid-voyage. In September 1578, the ship passed south of Tierra del Fuego, the southern tip of South America, through the area now known as the Drake Passage. In June 1579, Drake landed somewhere north of Spain's northernmost claim in Alta California, presumably Drakes Bay. Drake completed the second complete circumnavigation of the world in a single vessel on September 1580, becoming the first commander to survive the entire circumnavigation.

Thomas Cavendish completed his circumnavigation between 1586 and 1588 in record time—in two years and 49 days, nine months faster than Drake. It was also the first deliberately planned voyage of the globe.

For the wealthy, long voyages around the world, such as was done by Ulysses S. Grant, became possible in the 19th century, and the two World Wars moved vast numbers of troops around the planet. However, it was the rise of commercial aviation in the late 20th century that made circumnavigation, when compared to the Magellan–Elcano expedition, quicker and safer.

Nautical

The nautical global and fastest circumnavigation record is currently held by a wind-powered vessel, the trimaran IDEC 3. The record was established by six sailors: Francis Joyon, Alex Pella, Clément Surtel, Gwénolé Gahinet, Sébastien Audigane and Bernard Stamm; who wrote themselves into history books on 26 January 2017, by circumnavigating the globe in 40 days, 23 hours, 30 minutes and 30 seconds. The absolute speed sailing record around the world followed the North Atlantic Ocean, Equator, South Atlantic Ocean, Southern Ocean, South Atlantic Ocean, Equator, North Atlantic Ocean route in an easterly direction.

Wind powered

The route of a typical modern sailing circumnavigation, via the Suez Canal and the Panama Canal is shown in red; its antipodes are shown in yellow.

The map on the right shows, in red, a typical, non-competitive, route for a sailing circumnavigation of the world by the trade winds and the Suez and Panama canals; overlaid in yellow are the points antipodal to all points on the route. It can be seen that the route roughly approximates a great circle, and passes through two pairs of antipodal points. This is a route followed by many cruising sailors, going in the western direction; the use of the trade winds makes it a relatively easy sail, although it passes through a number of zones of calms or light winds.

The route of a typical yacht racing circumnavigation is shown in red; its antipodes are shown in yellow.

In yacht racing, a round-the-world route approximating a great circle would be quite impractical, particularly in a non-stop race where use of the Panama and Suez Canals would be impossible. Yacht racing therefore defines a world circumnavigation to be a passage of at least 21,600 nautical miles (40,000 km) in length which crosses the equator, crosses every meridian and finishes in the same port as it starts. The second map on the right shows the route of the Vendée Globe round-the-world race in red; overlaid in yellow are the points antipodal to all points on the route. It can be seen that the route does not pass through any pairs of antipodal points. Since the winds in the higher southern latitudes predominantly blow west-to-east it can be seen that there are an easier route (west-to-east) and a harder route (east-to-west) when circumnavigating by sail; this difficulty is magnified for square-rig vessels due to the square rig's dramatic lack of upwind ability when compared to a more modern Bermuda rig.

For around the world sailing records, there is a rule saying that the length must be at least 21,600 nautical miles calculated along the shortest possible track from the starting port and back that does not cross land and does not go below 63°S. It is allowed to have one single waypoint to lengthen the calculated track. The equator must be crossed.

The solo wind powered circumnavigation record of 42 days, 16 hours, 40 minutes and 35 seconds was established by François Gabart on the maxi-multihull sailing yacht MACIF and completed on 7 December 2017. The voyage followed the North Atlantic Ocean, Equator, South Atlantic Ocean, Southern Ocean, South Atlantic Ocean, Equator, North Atlantic Ocean route in an easterly direction.

Mechanically powered

Since the advent of world cruises in 1922, by Cunard's Laconia, thousands of people have completed circumnavigations of the globe at a more leisurely pace. Typically, these voyages begin in New York City or Southampton, and proceed westward. Routes vary, either travelling through the Caribbean and then into the Pacific Ocean via the Panama Canal, or around Cape Horn. From there ships usually make their way to Hawaii, the islands of the South Pacific, Australia, New Zealand, then northward to Hong Kong, South East Asia, and India. At that point, again, routes may vary: one way is through the Suez Canal and into the Mediterranean; the other is around Cape of Good Hope and then up the west coast of Africa. These cruises end in the port where they began.

In 1960, the American nuclear-powered submarine USS Triton circumnavigated the globe in 60 days, 21 hours for Operation Sandblast.

The current circumnavigation record in a powered boat of 60 days 23 hours and 49 minutes was established by a voyage of the wave-piercing trimaran Earthrace which was completed on 27 June 2008. The voyage followed the North Atlantic Ocean, Panama Canal, Pacific Ocean, Indian Ocean, Suez Canal, Mediterranean Sea route in a westerly direction.

Aviation

In 1922 Norman Macmillan (RAF officer), Major W T Blake and Geoffrey Malins made an unsuccessful attempt to fly a Daily News-sponsored round-the-world flight. The first aerial circumnavigation of the planet was flown in 1924 by aviators of the U.S. Army Air Service in a quartet of Douglas World Cruiser biplanes. The first non-stop aerial circumnavigation of the planet was flown in 1949 by Lucky Lady II, a United States Air Force Boeing B-50 Superfortress.

Since the development of commercial aviation, there are regular routes that circle the globe, such as Pan American Flight One (and later United Airlines Flight One). Today planning such a trip through commercial flight connections is simple.

The first lighter-than-air aircraft of any type to circumnavigate under its own power was the rigid airship LZ 127 Graf Zeppelin, which did so in 1929.

Aviation records take account of the wind circulation patterns of the world; in particular the jet streams, which circulate in the northern and southern hemispheres without crossing the equator. There is therefore no requirement to cross the equator, or to pass through two antipodal points, in the course of setting a round-the-world aviation record. Thus, for example, Steve Fossett's global circumnavigation by balloon was entirely contained within the southern hemisphere.

For powered aviation, the course of a round-the-world record must start and finish at the same point and cross all meridians; the course must be at least 36,770 kilometres (19,850 nmi) long (which is approximately the length of the Tropic of Cancer). The course must include set control points at latitudes outside the Arctic and Antarctic circles.

In ballooning, which is at the mercy of the winds, the requirements are even more relaxed. The course must cross all meridians, and must include a set of checkpoints which are all outside of two circles, chosen by the pilot, having radii of 3,335.85 kilometres (2,072.80 mi) and enclosing the poles (though not necessarily centred on them).

Astronautics

The first person to fly in space, Yuri Gagarin, also became the first person to complete an orbital spaceflight in the Vostok 1 spaceship within 2 hours in 1961.

Flight started at 63° E and ended 45° E longitude; thus Gagarin did not circumnavigate Earth completely.

Gherman Titov in the Vostok 2 was the first human to circumnavigate Earth in spaceflight and made 17.5 orbits.

Human-powered

Jason Lewis of Expedition 360 pedalling his boat Moksha on the River Thames in London, shortly before completing the first human-powered circumnavigation of the Earth (2007)

According to adjudicating bodies Guinness World Records and Explorersweb, Jason Lewis completed the first human-powered circumnavigation of the globe on 6 October 2007. This was part of a thirteen-year journey entitled Expedition 360.

In 2012, Turkish-born American adventurer Erden Eruç completed the first entirely solo human-powered circumnavigation, travelling by rowboat, sea kayak, foot and bicycle from 10 July 2007 to 21 July 2012, crossing the equator twice, passing over 12 antipodal points, and logging 66,299 kilometres (41,196 mi) in 1,026 days of travel time, excluding breaks.

National Geographic lists Colin Angus as being the first to complete a global circumnavigation. However, his journey did not cross the equator or hit the minimum of two antipodal points as stipulated by the rules of Guinness World Records and AdventureStats by Explorersweb.

People have both bicycled and run around the world, but the oceans have had to be covered by air or sea travel, making the distance shorter than the Guinness guidelines. To go from North America to Asia on foot is theoretically possible but very difficult. It involves crossing the Bering Strait on the ice, and around 3,000 kilometres (1,900 mi) of roadless swamped or freezing cold areas in Alaska and eastern Russia. No one has so far travelled all of this route by foot. David Kunst was the first verified person to walk around the world between 20 June 1970 and 5 October 1974.

Notable circumnavigations

Main article: List of circumnavigations
 
A replica of Magellan and Elcano's Nao Victoria, the first vessel to circumnavigate the planet
 
In 2012, the Swiss boat PlanetSolar became the first ever solar electric vehicle to circumnavigate the globe.

Maritime

  • The Castilian ('Spanish') Magellan-Elcano expedition of August 1519 to 8 September 1522, started by Portuguese navigator Fernão de Magalhães (Ferdinand Magellan) and completed by Spanish Basque navigator Juan Sebastián Elcano after Magellan's death, was the first global circumnavigation (see Victoria).
  • The survivors of García Jofre de Loaísa's Spanish expedition 1525–1536, including Andrés de Urdaneta and Hans von Aachen, who was also one of the 18 survivors of Magellan's expedition, making him the first to circumnavigate the world twice.
  • Francis Drake carried out the second circumnavigation of the world in a single expedition (and on a single independent voyage), from 1577 to 1580.
  • Jeanne Baret is the first woman to complete a voyage of circumnavigation, in 1766–1769.
  • John Hunter commanded the first ship to circumnavigate the World starting from Australia, between 2 September 1788 and 8 May 1789, with one stop in Cape Town to load supplies for the colony of New South Wales.
  • HMS Driver completed the first circumnavigation by a steam ship in 1845–1847.
  • The Spanish frigate Numancia, commanded by Juan Bautista Antequera y Bobadilla, completed the first circumnavigation by an ironclad in 1865–1867.
  • Joshua Slocum completed the first single-handed circumnavigation in 1895–1898.
  • In 1960, the U.S. Navy nuclear-powered submarine USS Triton (SSRN-586) completed the submerged circumnavigation.
  • In 1969, Robin Knox-Johnston became the first person to complete a single-handed non-stop circumnavigation.
  • In 1999, Jesse Martin became the youngest recognized person to complete an unassisted, non-stop, circumnavigation, at the age of 18.
  • In 2001, the U.S. Coast Guard USCGC Sherman (WHEC-720) became the first Coast Guard vessel to circumnavigate the globe.
  • In 2012, PlanetSolar became the first ever solar electric vehicle to circumnavigate the globe.
  • In 2012, Laura Dekker became the youngest person to circumnavigate the globe single-handed, with stops, at the age of 16.
  • In 2017, trimaran IDEC 3 with sailors: Francis Joyon, Alex Pella, Clément Surtel, Gwénolé Gahinet, Sébastien Audigane and Bernard Stamm completes the fastest circumnavigation of the globe ever; in 40 days, 23 hours, 30 minutes and 30 seconds. The voyage followed the North Atlantic Ocean, Equator, South Atlantic Ocean, Southern Ocean, South Atlantic Ocean, Equator, North Atlantic Ocean route in an easterly direction.
  • In 2022, the MV Astra, a former Swedish Sea Rescue Society ship became the first sub-24m motor-powered vessel to circumnavigate the globe via the southern capes.

Aviation

Land

  • In 1841–1842 Sir George Simpson made the first "land circumnavigation", crossing Canada and Siberia and returning to London.
  • Ranulph Fiennes and Charlie Burton are credited with the first north–south circumnavigation of the Earth.

Human

  • On 13 June 2003, Robert Garside completed the first recognized run around the world, taking 5+1⁄2 years; the run was authenticated in 2007 by Guinness World Records after five years of verification.
  • On 6 October 2007, Jason Lewis completed the first human-powered circumnavigation of the globe (including human-powered sea crossings).
  • On 21 July 2012, Erden Eruç completed the first entirely solo human-powered circumnavigation of the globe.
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British philosophy

From Wikipedia, the free encyclopedia
 
David Hume, a profoundly influential 18th-century Scottish philosopher

British philosophy refers to the philosophical tradition of the British people. "The native characteristics of British philosophy are these: common sense, dislike of complication, a strong preference for the concrete over the abstract and a certain awkward honesty of method in which an occasional pearl of poetry is embedded".

Medieval

Anselm of Canterbury

A colourised 16th-century portrait of Anselm, Archbishop of Canterbury

Saint Anselm of Canterbury (c. 1033 – 1109) was an important philosopher and theologian of the Catholic Church, who held the office of Archbishop of Canterbury from 1093 to 1109. Anselm is famed as the originator of the ontological argument for the existence of God and of the satisfaction theory of atonement. Anselm's works are considered philosophical as well as theological since they endeavour to render Christian tenets of faith, traditionally taken as a revealed truth, as a rational system.

William of Sherwood

Main article: William of Sherwood

William of Sherwood (c. 1200 – c. 1272) was a medieval English scholastic philosopher, logician, and teacher. Little is known of his life, but he is thought to have studied in Paris and he was a master at Oxford in 1252. He was the author of two books which were an important influence on the development of scholastic logic: Introductiones in Logicam (Introduction to Logic), and Syncategoremata. These are the first known works to deal in a systematic way with what is now called supposition theory, and were influential on the development of logic in both England and on the continent. According to Roger Bacon, Sherwood was among "the more famous wise men of Christendom", of whom he names another as Albertus Magnus. Bacon judged Sherwood to be "much wiser than Albert".

Roger Bacon

Main article: Roger Bacon

Roger Bacon (c. 1214–1294), also known as Doctor Mirabilis (Latin: "Wondrous Doctor"), was an English philosopher and Franciscan friar who placed considerable emphasis on empirical methods. He is sometimes credited as one of the earliest European advocates of the modern scientific method inspired by the works of Plato and Aristotle via early Islamic scientists such as Avicenna and Averroes.

Duns Scotus

Main article: Duns Scotus

John Duns Scotus (c. 1265 – 8 November 1308) was an important philosopher and theologian of the High Middle Ages. Scotus was born around 1265, at Duns, in Berwickshire, Scotland. In 1291 he was ordained as a priest in Northampton, England. A note in Codex 66 of Merton College, Oxford, records that Scotus "flourished at Cambridge, Oxford and Paris". He died in Cologne in 1308. He is buried in the "Minoritenkirche", the Church of the Franciscans (or Minor Friars) in Cologne. He was beatified by Pope John Paul II on 20 March 1993.

Nicknamed Doctor Subtilis (the subtle doctor), he is well known for the "univocity of being," the formal distinction, and the idea of haecceity. The univocity of being holds that existence is the most abstract concept we have and is applicable to everything that exists. The formal distinction is a way of distinguishing between different aspects of the same thing such that the distinction is intermediate between what is merely conceptual, and what is fully real or mind-independent. Haecceity (from the Latin haecceitas) is the idea of "thisness," a concept which denotes the discrete qualities, properties or characteristics of a thing which make it a particular thing.

William of Ockham

Main article: William of Ockham

William of Ockham (c. 1288 – c. 1348) was an English Franciscan friar and scholastic philosopher. He is perhaps most well known for his principle of parsimony, famously known as Occam's razor. This actual term is claimed not to appear in his writings, but rather summarizes the principle he expressed in passages such as Numquam ponenda est pluralitas sine necessitate [Plurality must never be posited without necessity] and Frustra fit per plura quod potest fieri per pauciora (It is futile to do with more things that which can be done with fewer). Generally it refers to distinguishing between two hypotheses either by "shaving away" unnecessary assumptions or cutting apart two similar conclusions.

The words often attributed to Occam: entia non sunt multiplicanda praeter necessitatem ("entities must not be multiplied beyond necessity") are absent in his extant works; This particular phrasing comes from John Punch who used it in describing a "common axiom" (axioma vulgare) of the Scholastics.

Modern

Francis Bacon

Main article: Francis Bacon
 
Francis Bacon

Francis Bacon (1561–1626) was an Englishman who was a statesman, scientist, lawyer, jurist and author in addition to being a philosopher. He famously died of pneumonia contracted while studying the effects of freezing on the preservation of meat. He served both as Attorney General and Lord Chancellor of England. Although his political career ended in disgrace, he remained extremely influential through his works, especially as philosophical advocate and practitioner of the scientific method and pioneer in the scientific revolution.

Bacon has been called the father of empiricism. His works established and popularized deductive methodologies for scientific inquiry, often called the Baconian method or simply, the scientific method. His demand for a planned procedure of investigating all things natural marked a new turn in the rhetorical and theoretical framework for science, much of which still surrounds conceptions of proper methodology today. His dedication probably led to his death, so bringing him into a rare historical group of scientists who were killed by their own experiments.

Thomas Hobbes

Main article: Thomas Hobbes

Thomas Hobbes (1588–1679) was an English philosopher, remembered today for his work on political philosophy. His 1651 book Leviathan established the foundation for most of Western political philosophy from the perspective of social contract theory.

Hobbes was a champion of absolutism for the sovereign but he also developed some of the fundamentals of European liberal thought: the right of the individual; the natural equality of all men; the artificial character of the political order (which led to the later distinction between civil society and the state); the view that all legitimate political power must be "representative" and based on the consent of the people; and a liberal interpretation of law which leaves people free to do whatever the law does not explicitly forbid.

Hobbes also contributed to a diverse array of fields, including history, geometry, physics of gases, theology, ethics, general philosophy, and political science. His account of human nature as self-interested cooperation has proved to be an enduring theory in the field of philosophical anthropology. He was one of the key founders of philosophical materialism.

The classic trio of British empiricists

The three 'classic' British empiricists in the early modern era were John Locke, George Berkeley, and David Hume. The term "British empiricism" refers to the philosophical tradition in Britain that was epitomised by these thinkers (though this tradition did have precursors in Britain stretching back to Roger Bacon). Berkeley, despite being Irish, was referred to as British as County Kilkenny, where he lived in Ireland, was a part of the United Kingdom of Great Britain and Ireland at the time.

John Locke

Main article: John Locke
 
John Locke

John Locke (1632–1704) was an empiricist at the beginning of the Modern period of philosophy. As such (and in contrast to René Descartes), he held that all of the objects of the understanding are ideas, where ideas exist in the mind. One of his goals in his work An Essay Concerning Human Understanding is to trace the origin of ideas. There are no innate ideas “stamped upon the mind” from birth, and all knowledge is rooted in experience. Further, there are also simple ideas and complex ideas. Simple ideas enter by the senses, and they are simple and unmixed. Complex ideas are simple ideas that have been combined and related together using the abstracting activity of the mind.

John Locke embodied the idea of religious tolerance and said "no mans knowledge can exceed his experience" based on his background in epistemology.

Locke is also responsible for an early theory of personal identity. He thought that our being the same person from one time to another consists, not in our having the same soul or the same body, but rather the same series of psychological connections. For Locke, to be a person is to be an intelligent thinking being that can know itself as itself, the same thinking thing in different times and places.

George Berkeley

Main article: George Berkeley

George Berkeley (1685–1753) was an Irish philosopher who served as Bishop of Cloyne from 1734 until his death. He was a British empiricist, an immaterialist, and an idealist. Many of his most important ideas were first put forth in A Treatise Concerning the Principles of Human Knowledge, a work which was critical of John Locke's philosophy. Berkeley agreed with Locke that there was an outside world which caused the ideas within the mind, but Berkeley sought to prove that the outside world was also composed solely of ideas. Berkeley thought that the ideas that we possessed could only resemble other ideas (not physical objects) and thus the external world consisted not of physical form, but rather of ideas. This world was given logic and regularity by some other force, which Berkeley concluded was God.

Berkeley is famous for his motto "esse est percipi aut percipere", or otherwise, "to exist is to be perceived, or to perceive". This means that there are no things other than ideas and the minds that house them. There is no such thing as a mind-independent entity.

David Hume

Main article: David Hume
See also: Scottish Enlightenment

David Hume (1711–1776) was a Scottish philosopher, economist, and historian. His major works, A Treatise of Human Nature (1739–1740), the An Enquiry concerning Human Understanding (1748), An Enquiry Concerning the Principles of Morals (1751), and Dialogues Concerning Natural Religion (1779) remain widely influential. His ideas regarding free will and determinism, causation, personal identity, induction, and morality still inspire discussion.

Hume famously described the problem of induction. He argues that inductive reasoning cannot be rationally employed, since, in order to justify induction, one would either have to provide a sound deductive argument or an inductively strong argument. But there is no sound deductive argument for induction, and to ask for an inductive argument to justify induction would be to beg the question.

Hume's problem of causation is related to his problem of induction. He held that there is no empirical access to the supposed necessary connection between cause and effect. In seeking to justify the belief that A causes B, one would point out that, in the past, B has always closely followed A in both space and time. But the special necessary connection that is supposed to be causation is never given to us in experience. We only observe a constant conjunction of events, with no necessity whatsoever.

In personal identity, Hume was a bundle theorist. He said that there is no robust self to which properties adhere. Experience only shows us that there is only a bundle of perceptions.

Adam Smith

Main article: Adam Smith

Adam Smith (1723–1790) was a Scottish moral philosopher and a pioneer of political economics. Smith wrote The Theory of Moral Sentiments and An Inquiry into the Nature and Causes of the Wealth of Nations. The latter, usually abbreviated as The Wealth of Nations, is considered his magnum opus and the first modern work of economics. Smith is widely cited as the father of modern economics.

Smith studied moral philosophy at the University of Glasgow and the University of Oxford. After graduating, he delivered a successful series of public lectures at Edinburgh, leading him to collaborate with David Hume during the Scottish Enlightenment. Smith obtained a professorship at Glasgow teaching moral philosophy, and during this time he wrote and published The Theory of Moral Sentiments.

19th century

Jeremy Bentham

Main article: Jeremy Bentham

Jeremy Bentham (1748–1832) is well known for beginning the tradition of classical utilitarianism in Britain. Utilitarianism is a consequentialist theory of normative ethics which holds that an act is morally right if and only if that act maximizes happiness or pleasure. Classical utilitarianism is said to be hedonistic because it regards pleasure as the only intrinsic good and pain as the only intrinsic evil.

Utilitarianism was described by Bentham as "the greatest happiness or greatest felicity principle". Bentham's utilitarianism is known for arguing that the felicific calculus should be used to determine the rightness and wrongness of acts. It does this by measuring the amount of pain and pleasure for various acts. Bentham thought that pleasure and pain be broke down in distinct units called hedons and dolors.

John Stuart Mill

Main article: John Stuart Mill
 
John Stuart Mill

John Stuart Mill (1806–1873) was an influential contributor to social theory, political theory, and political economy. His conception of liberty justified the freedom of the individual in opposition to unlimited state control.

Mill also continued Bentham's tradition of advancing and defending utilitarianism. Mill's book Utilitarianism is a philosophical defense of utilitarianism. The essay first appeared as a series of three articles published in Fraser's Magazine in 1861; the articles were collected and reprinted as a single book in 1863.

Henry Sidgwick

Main article: Henry Sidgwick

Henry Sidgwick (1838–1900) also focused on utilitarian ethics and was one of the founders and first president of the Society for Psychical Research, was a member of the Metaphysical Society, and promoted the higher education of women. The Methods of Ethics is a book on utilitarianism written by Sidgwick that was first published in 1874. The Stanford Encyclopedia of Philosophy indicates that The Methods of Ethics "in many ways marked the culmination of the classical utilitarian tradition." Well-known contemporary utilitarian philosopher Peter Singer has said that the Methods "is simply the best book on ethics ever written."

British idealism

Main article: British idealism

As an area of absolute idealism, British idealism was a philosophical movement that was influential in Britain from the mid-nineteenth century to the early twentieth century. Important representatives included T. H. Green, F. H. Bradley, Bernard Bosanquet, J. M. E. McTaggart, H. H. Joachim, J. H. Muirhead, and G. R. G. Mure. Two British philosophers, G. E. Moore and Bertrand Russell, were brought up in this tradition and then reacted against it by pioneering analytic philosophy.

20th century and beyond

Analytic philosophy

Main article: Analytic philosophy

Analytic philosophy was based on traditional British empiricism, updated to accommodate the new developments in logic pioneered by German mathematician Gottlob Frege. It has dominated philosophy in the English-speaking world since the early 20th century.

G. E. Moore

Main article: G. E. Moore

George Edward Moore (1873–1958) was an English philosopher. One of the founders of the analytic tradition, he led the British 'revolt against idealism' at the turn of the twentieth century, along with Bertrand Russell - while Russell is better known, he stated that it was in fact Moore who "led the way".

Moore is best known today for his defence of ethical non-naturalism, his emphasis on common sense in philosophical method, and the paradox that bears his name. He was admired by and influential among other philosophers, and also by the Bloomsbury Group, but is (unlike his colleague Russell) mostly unknown today outside of academic philosophy. Moore's essays are known for his clear, circumspect writing style, and for his methodical and patient approach to philosophical problems. He was critical of philosophy for its lack of progress, which he believed was in stark contrast to the dramatic advances in the natural sciences since the Renaissance. He often praised the analytic reasoning of Thales of Miletus, an early Greek philosopher, for his analysis of the meaning of the term "landscaping". Moore thought Thales' reasoning was one of the few historical examples of philosophical inquiry resulting in practical advances. Among his most famous works are his book Principia Ethica, and his essays, "The Refutation of Idealism", "A Defence of Common Sense", and "A Proof of the External World".

He was president of the Aristotelian Society from 1918 to 1919.

Bertrand Russell

Main article: Bertrand Russell
 
Bertrand Russell

Bertrand Russell (1872–1970) led the British "revolt against idealism" in the early 1900s, along with G. E. Moore. He was influenced by Gottlob Frege, and was the mentor of Ludwig Wittgenstein. He is widely held to be one of the 20th century's premier logicians. He co-authored, with Alfred North Whitehead, Principia Mathematica, an attempt to derive all mathematical truths from a set of axioms using rules of inference in symbolic logic. His philosophical essay "On Denoting" has been considered a "paradigm of philosophy." Both works have had a considerable influence on logic, mathematics, set theory, linguistics, and philosophy.

Russell's theory of descriptions has been profoundly influential in the philosophy of language and the analysis of definite descriptions. His theory was first developed in his 1905 paper "On Denoting".

Russell was a prominent anti-war activist; he championed free trade and anti-imperialism. Russell went to prison for his pacifist activism during World War I. Later, he campaigned against Adolf Hitler, then criticised Stalinist totalitarianism, attacked the United States of America's involvement in the Vietnam War, and finally became an outspoken proponent of nuclear disarmament.

In 1950, Russell was awarded the Nobel Prize in Literature, "in recognition of his varied and significant writings in which he champions humanitarian ideals and freedom of thought."

A. J. Ayer

Main article: A. J. Ayer

Sir Alfred Jules Ayer (29 October 1910, London – 27 June 1989, London), better known as A. J. Ayer or "Freddie" to friends, was a British analytic philosopher known for his promotion of logical positivism, particularly in his books Language, Truth and Logic (1936) and The Problem of Knowledge (1956).

Ordinary language philosophy

Main article: Ordinary language philosophy

Ordinary language philosophy is a philosophical school that approaches traditional philosophical problems as rooted in misunderstandings that philosophers develop by forgetting what words mean in their everyday use.

This approach typically involves eschewing philosophical theories in favour of close attention to the detail of everyday language. Sometimes also called "Oxford philosophy", it is generally associated with the work of a number of mid-century Oxford professors: mainly J. L. Austin, but also Gilbert Ryle, H. L. A. Hart, and P.F. Strawson.

It was a major philosophic school between 1930 and 1970.

Contemporary times

Recent British philosophers particularly active in the philosophy of religion have included Antony Flew, C. S. Lewis, and John Hick.

Important moral and political philosophers have included R. M. Hare, Alasdair MacIntyre, and Roger Scruton.

Other recent figures in the British analytic tradition include David Wiggins, Derek Parfit, and P. F. Strawson, who have focused on fields such as metaphysics, philosophy of mind, logic, and the philosophy of language.

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Suxamethonium chloride

From Wikipedia, the free encyclopedia

Suxamethonium chloride
Suxamethonium-chloride-2D-skeletal.svg
Suxamethonium chloride ball-and-stick.png
Clinical data
Pronunciation/ˌsʌksɪnɪlˈkoʊliːn/
Trade namesQuelicin, Anectine, others
AHFS/Drugs.comMonograph
License data
Pregnancy
category
  • AU: A
Routes of
administration		Intravenous, intramuscular
ATC code
Legal status
Legal status
  • AU: S4 (Prescription only)
  • UK: POM (Prescription only)
  • US: ℞-only
Pharmacokinetic data
BioavailabilityNA
MetabolismBy pseudocholinesterase, to succinylmonocholine and choline
Onset of action30–60 sec (IV), 2–3 min (IM)
Duration of action< 10 min (IV), 10–30 min (IM)
ExcretionKidney (10%)
Identifiers

CAS Number
PubChem CID
IUPHAR/BPS
DrugBank
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
CompTox Dashboard (EPA)
Chemical and physical data
FormulaC14H30Cl2N2O4
Molar mass361.30 g·mol−1
3D model (JSmol)

Suxamethonium chloride, also known as suxamethonium or succinylcholine, or simply sux by medical abbreviation, is a medication used to cause short-term paralysis as part of general anesthesia. This is done to help with tracheal intubation or electroconvulsive therapy. It is administered by injection, either into a vein or into a muscle. When used in a vein, onset of action is generally within one minute and effects last for up to 10 minutes.

Common side effects include low blood pressure, increased saliva production, muscle pain, and rash. Serious side effects include malignant hyperthermia, hyperkalemia and allergic reactions. It is not recommended in people who are at risk of high blood potassium or a history of myopathy. Use during pregnancy appears to be safe for the baby.

Suxamethonium is in the neuromuscular blocker family of medications and is of the depolarizing type. It works by blocking the action of acetylcholine on skeletal muscles.

Suxamethonium was described as early as 1906 and came into medical use in 1951. It is on the World Health Organization's List of Essential Medicines. Suxamethonium is available as a generic medication.

Medical uses

A vial of suxamethonium chloride

Succinylcholine chloride injection is indicated, in addition to general anesthesia, to facilitate tracheal intubation and to provide skeletal muscle relaxation during surgery or mechanical ventilation.

Its medical uses are limited to short-term muscle relaxation in anesthesia and intensive care, usually for facilitation of endotracheal intubation. It is popular in emergency medicine due to its rapid onset and brief duration of action. The former is a major point of consideration in the context of trauma care, where endotracheal intubation may need to be completed very quickly. The latter means that, should attempts at endotracheal intubation fail and the person cannot be ventilated, there is a prospect for neuromuscular recovery and the onset of spontaneous breathing before low blood oxygen levels occurs. It may be better than rocuronium in people without contraindications due to its faster onset of action and shorter duration of action.

Suxamethonium is also commonly used as the sole muscle relaxant during electroconvulsive therapy, favoured for its short duration of action.

Suxamethonium is quickly degraded by plasma butyrylcholinesterase and the duration of effect is usually in the range of a few minutes. When plasma levels of butyrylcholinesterase are greatly diminished or an atypical form is present (an otherwise harmless inherited disorder), paralysis may last much longer, as is the case in liver failure or in neonates.

It is recommended that the vials be stored at a temperature between 2°-8 °C. The multi-dose vials are stable for up to 14 days at room temperature without significant loss of potency. Unless otherwise indicated in the prescribing information, room temperature for storage of medications is 15°-25 °C (59°-77 °F).

Side effects

Side effects include malignant hyperthermia, muscle pains, acute rhabdomyolysis with high blood levels of potassium, transient ocular hypertension, constipation and changes in cardiac rhythm, including slow heart rate, and cardiac arrest. In people with neuromuscular disease or burns, an injection of suxamethonium can lead to a large release of potassium from skeletal muscles, potentially resulting in cardiac arrest. Conditions having susceptibility to suxamethonium-induced high blood potassium are burns, closed head injury, acidosis, Guillain–Barré syndrome, cerebral stroke, drowning, severe intra-abdominal sepsis, massive trauma, myopathy, and tetanus.

Suxamethonium does not produce unconsciousness or anesthesia, and its effects may cause considerable psychological distress while simultaneously making it impossible for a patient to communicate. Therefore, administration of the drug to a conscious patient is contraindicated.

Hyperkalemia

The side effect of high blood potassium may occur because the acetylcholine receptor is propped open, allowing continued flow of potassium ions into the extracellular fluid. A typical increase of potassium ion serum concentration on administration of suxamethonium is 0.5 mmol per liter.The increase is transient in otherwise healthy patients. The normal range of potassium is 3.5 to 5 mEq per liter. High blood potassium does not generally result in adverse effects below a concentration of 6.5 to 7 mEq per liter. Therefore, the increase in serum potassium level is usually not catastrophic in otherwise healthy patients. Severely high blood levels of potassium can cause changes in cardiac electrophysiology, which, if severe, can result in arrhythmias and even cardiac arrest.

Malignant hyperthermia

Malignant hyperthermia (MH) from suxamethonium administration can result in a drastic and uncontrolled increase in skeletal muscle oxidative metabolism. This overwhelms the body's capacity to supply oxygen, remove carbon dioxide, and regulate body temperature, eventually leading to circulatory collapse and death if not treated quickly.

Susceptibility to malignant hyperthermia is often inherited as an autosomal dominant disorder, for which there are at least six genetic loci of interest, the most prominent being the ryanodine receptor gene (RYR1). MH susceptibility is phenotype and genetically related to central core disease (CCD), an autosomal dominant disorder characterized both by MH symptoms and by myopathy. MH is usually unmasked by anesthesia, or when a family member develops the symptoms. There is no simple, straightforward test to diagnose the condition. When MH develops during a procedure, treatment with dantrolene sodium is usually initiated; dantrolene and the avoidance of suxamethonium administration in susceptible people have markedly reduced the mortality from this condition.

Apnea

See also: Pseudocholinesterase deficiency

The normal short duration of action of suxamethonium is due to the rapid metabolism of the drug by non-specific plasma cholinesterases. However plasma cholinesterase activity is reduced in some people due to either genetic variation or acquired conditions, which results in a prolonged duration of neuromuscular block. Genetically, ninety six percent of the population have a normal (Eu:Eu) genotype and block duration; however, some people have atypical genes (Ea, Es, Ef) which can be found in varying combinations with the Eu gene, or other atypical genes (see Pseudocholinesterase deficiency). Such genes will result in a longer duration of action of the drug, ranging from 20 minutes up to several hours. Acquired factors that affect plasma cholinesterase activity include pregnancy, liver disease, kidney failure, heart failure, thyrotoxicosis, and cancer, as well as a number of other drugs.

If unrecognized by a clinician it could lead to awareness if anesthesia is discontinued whilst still paralyzed or hypoxemia (and potentially fatal consequences) if artificial ventilation is not maintained. Normal treatment is to maintain sedation and ventilate the patient on an intensive care unit until muscle function has returned. Blood testing for cholinesterase function can be performed.

Mivacurium, a non-depolarizing neuromuscular blocking drug, is also metabolized via the same route with a similar clinical effect in patients deficient in plasma cholinesterase activity.[medical citation needed]

Deliberate induction of conscious apnea using this drug led to its use as a form of aversion therapy in the 1960s and 1970s in some prison and institutional settings. This use was discontinued after negative publicity concerning the terrifying effects on subjects of this treatment and ethical questions about the punitive use of painful aversion.

Mechanism of action

There are two phases to the blocking effect of suxamethonium.

Phase 1 block

Phase 1 blocking has the principal paralytic effect. Binding of suxamethonium to the nicotinic acetylcholine receptor results in opening of the receptor's monovalent cation channel; a disorganized depolarization of the motor end-plate occurs and calcium is released from the sarcoplasmic reticulum.

In normal skeletal muscle, acetylcholine dissociates from the receptor following depolarization and is rapidly hydrolyzed by acetylcholinesterase. The muscle cell is then ready for the next signal.

Suxamethonium has a longer duration of effect than acetylcholine, and is not hydrolyzed by acetylcholinesterase. By maintaining the membrane potential above threshold, it does not allow the muscle cell to repolarize. When acetylcholine binds to an already depolarized receptor, it cannot cause further depolarization. 

Calcium is removed from the muscle cell cytoplasm independent of repolarization (depolarization signaling and muscle contraction are independent processes). As the calcium is taken up by the sarcoplasmic reticulum, the muscle relaxes. This explains muscle flaccidity rather than tetany following fasciculations.

The results are membrane depolarization and transient fasciculations, followed by flaccid paralysis.

Phase 2 block

While this phase is not abnormal and is a part of its mechanism of action, it is undesirable during surgery, due to the inability to depolarize the cell again. Often, patients must be on a ventilator for hours if Phase 2 block occurs. It is caused by the blood concentration of suxamethonium exceeding the therapeutic window. Desensitization occurs at the nerve terminal, and the myocyte becomes less sensitive to acetylcholine; the membrane repolarizes and cannot be depolarized again.

Chemistry

Suxamethonium is an odorless, white crystalline substance. Aqueous solutions have a pH of about 4. The dihydrate melts at 160 °C, whereas the anhydrous melts at 190 °C. It is highly soluble in water (1 gram in about 1 mL), soluble in ethyl alcohol (1 gram in about 350 mL), slightly soluble in chloroform, and practically insoluble in ether. Suxamethonium is a hygroscopic compound. The compound consists of two acetylcholine molecules that are linked by their acetyl groups. It can also be viewed as a central moiety of succinic acid with two choline moieties, one on each end.

History

Suxamethonium was first discovered in 1906 by Reid Hunt and René de M. Taveau. When studying the drug, animals were given curare and thus they missed the neuromuscular blocking properties of suxamethonium. Instead in 1949 an Italian group led by Daniel Bovet was first to describe succinylcholine induced paralysis. The clinical introduction of suxamethonium was described in 1951 by several groups. Papers published by Stephen Thesleff and Otto von Dardel in Sweden are important but also to be mentioned is work by Bruck, Mayrhofer and Hassfurther in Austria, Scurr and Bourne in UK, and Foldes in America.

Abuse

Dubai authorities deem that the murder of Hamas operative Mahmoud al-Mabhouh was carried out on their soil by Mossad agents with the use of suxamethonium chloride injection. Entering Dubai under false passports in 2010, the Mossad agents found al-Mabhouh at a hotel, immobilized him with the drug, electrocuted him, then suffocated him by pillow in an assassination. A high concentration of suxamethonium chloride was found in al-Mabhouh's body post-mortem. The incident triggered significant diplomatic crises in the Middle East, Europe, and Australia.

It was used by serial killer Efren Saldivar (1988-1998), and in the murder of Kathy Augustine (2006).

Brand names

It is available in German-speaking countries under the trade name Lysthenon among others.

Other animals

It is sometimes used in combination with pain medications and sedatives for euthanasia and immobilization of horses.

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