title: Anthropic principle

text: The anthropic principle has given rise to some confusion and controversy, partly because the phrase has been applied to several distinct ideas. All versions of the principle have been accused of discouraging the search for a deeper physical understanding of the universe. The anthropic principle is often criticized for lacking falsifiability and therefore its critics may point out that the anthropic principle is a non-scientific concept, even though the weak anthropic principle, "conditions that are observed in the universe must allow the observer to exist", is "easy" to support in mathematics and philosophy (i.e., it is a tautology or truism). However, building a substantive argument based on a tautological foundation is problematic. Stronger variants of the anthropic principle are not tautologies and thus make claims considered controversial by some and that are contingent upon empirical verification.


title: Anthropic principle

text: In 1961, Robert Dicke noted that the age of the universe, as seen by living observers, cannot be random. Instead, biological factors constrain the universe to be more or less in a "golden age", neither too young nor too old. If the universe were one tenth as old as its present age, there would not have been sufficient time to build up appreciable levels of metallicity (levels of elements besides hydrogen and helium) especially carbon, by nucleosynthesis. Small rocky planets did not yet exist. If the universe were 10 times older than it actually is, most stars would be too old to remain on the main sequence and would have turned into white dwarfs, aside from the dimmest red dwarfs, and stable planetary systems would have already come to an end. Thus, Dicke explained the coincidence between large dimensionless numbers constructed from the constants of physics and the age of the universe, a coincidence that inspired Dirac's varying-"G" theory.


title: Anthropic principle

text: Dicke later reasoned that the density of matter in the universe must be almost exactly the critical density needed to prevent the Big Crunch (the "Dicke coincidences" argument). The most recent measurements may suggest that the observed density of baryonic matter, and some theoretical predictions of the amount of dark matter account for about 30% of this critical density, with the rest contributed by a cosmological constant. Steven Weinberg gave an anthropic explanation for this fact: he noted that the cosmological constant has a remarkably low value, some 120 orders of magnitude smaller than the value particle physics predicts (this has been described as the "worst prediction in physics"). However, if the cosmological constant were only several orders of magnitude larger than its observed value, the universe would suffer catastrophic inflation, which would preclude the formation of stars, and hence life.


title: Anthropic principle

text: The observed values of the dimensionless physical constants (such as the fine-structure constant) governing the four fundamental interactions are balanced as if fine-tuned to permit the formation of commonly found matter and subsequently the emergence of life. A slight increase in the strong interaction would bind the dineutron and the diproton and convert all hydrogen in the early universe to helium; likewise, an increase in the weak interaction also would convert all hydrogen to helium. Water, as well as sufficiently long-lived stable stars, both essential for the emergence of life as we know it, would not exist. More generally, small changes in the relative strengths of the four fundamental interactions can greatly affect the universe's age, structure, and capacity for life.


title: Anthropic principle

text: The phrase "anthropic principle" first appeared in Brandon Carter's contribution to a 1973 Kraków symposium honouring Copernicus's 500th birthday. Carter, a theoretical astrophysicist, articulated the Anthropic Principle in reaction to the Copernican Principle, which states that humans do not occupy a privileged position in the Universe. Carter said: "Although our situation is not necessarily "central", it is inevitably privileged to some extent." Specifically, Carter disagreed with using the Copernican principle to justify the Perfect Cosmological Principle, which states that all large regions "and times" in the universe must be statistically identical. The latter principle underlay the steady-state theory, which had recently been falsified by the 1965 discovery of the cosmic microwave background radiation. This discovery was unequivocal evidence that the universe has changed radically over time (for example, via the Big Bang).


title: Anthropic principle

text: Carter defined two forms of the anthropic principle, a "weak" one which referred only to anthropic selection of privileged spacetime locations in the universe, and a more controversial "strong" form that addressed the values of the fundamental constants of physics.


title: Anthropic principle

text: One reason this is plausible is that there are many other places and times in which we can imagine finding ourselves. But when applying the strong principle, we only have one universe, with one set of fundamental parameters, so what exactly is the point being made? Carter offers two possibilities: First, we can use our own existence to make "predictions" about the parameters. But second, "as a last resort", we can convert these predictions into "explanations" by assuming that there "is" more than one universe, in fact a large and possibly infinite collection of universes, something that is now called the multiverse ("world ensemble" was Carter's term), in which the parameters (and perhaps the laws of physics) vary across universes. The strong principle then becomes an example of a selection effect, exactly analogous to the weak principle. Postulating a multiverse is certainly a radical step, but taking it could provide at least a partial answer to a question seemingly out of the reach of normal science: "Why do the fundamental laws of physics take the particular form we observe and not another?"


title: Anthropic principle

text: Since Carter's 1973 paper, the term "anthropic principle" has been extended to cover a number of ideas that differ in important ways from his. Particular confusion was caused by the 1986 book "The Anthropic Cosmological Principle" by John D. Barrow and Frank Tipler, which distinguished between a "weak" and "strong" anthropic principle in a way very different from Carter's, as discussed in the next section.


title: Anthropic principle

text: Carter was not the first to invoke some form of the anthropic principle. In fact, the evolutionary biologist Alfred Russel Wallace anticipated the anthropic principle as long ago as 1904: "Such a vast and complex universe as that which we know exists around us, may have been absolutely required [...] in order to produce a world that should be precisely adapted in every detail for the orderly development of life culminating in man." In 1957, Robert Dicke wrote: "The age of the Universe 'now' is not random but conditioned by biological factors [...] [changes in the values of the fundamental constants of physics] would preclude the existence of man to consider the problem."


title: Anthropic principle

text: Ludwig Boltzmann may have been one of the first in modern science to use anthropic reasoning. Prior to knowledge of the Big Bang Boltzmann's thermodynamic concepts painted a picture of a universe that had inexplicably low entropy. Boltzmann suggested several explanations, one of which relied on fluctuations that could produce pockets of low entropy or Boltzmann universes. While most of the universe is featureless in this model, to Boltzmann, it is unremarkable that humanity happens to inhabit a Boltzmann universe, as that is the only place where intelligent life could be.


title: Anthropic principle

text: Weak anthropic principle (WAP) (Carter): "... our location in the universe is "necessarily" privileged to the extent of being compatible with our existence as observers." Note that for Carter, "location" refers to our location in time as well as space.


title: Anthropic principle

text: Strong anthropic principle (SAP) (Carter): "[T]he universe (and hence the fundamental parameters on which it depends) must be such as to admit the creation of observers within it at some stage. To paraphrase Descartes, "cogito ergo mundus talis est"."The Latin tag ("I think, therefore the world is such [as it is]") makes it clear that "must" indicates a deduction from the fact of our existence; the statement is thus a truism.


title: Anthropic principle

text: In their 1986 book, "The Anthropic Cosmological Principle", John Barrow and Frank Tipler depart from Carter and define the WAP and SAP as follows:


title: Anthropic principle

text: Weak anthropic principle (WAP) (Barrow and Tipler): "The observed values of all physical and cosmological quantities are not equally probable but they take on values restricted by the requirement that there exist sites where carbon-based life can evolve and by the requirements that the universe be old enough for it to have already done so."Unlike Carter they restrict the principle to carbon-based life, rather than just "observers". A more important difference is that they apply the WAP to the fundamental physical constants, such as the fine-structure constant, the number of spacetime dimensions, and the cosmological constant—topics that fall under Carter's SAP.


title: Anthropic principle

text: Strong anthropic principle (SAP) (Barrow and Tipler): "The Universe must have those properties which allow life to develop within it at some stage in its history."This looks very similar to Carter's SAP, but unlike the case with Carter's SAP, the "must" is an imperative, as shown by the following three possible elaborations of the SAP, each proposed by Barrow and Tipler:


title: Anthropic principle

text: The philosophers John Leslie and Nick Bostrom reject the Barrow and Tipler SAP as a fundamental misreading of Carter. For Bostrom, Carter's anthropic principle just warns us to make allowance for "anthropic bias"—that is, the bias created by anthropic selection effects (which Bostrom calls "observation" selection effects)—the necessity for observers to exist in order to get a result. He writes:


title: Anthropic principle

text: Strong self-sampling assumption (SSSA) (Bostrom): "Each observer-moment should reason as if it were randomly selected from the class of all observer-moments in its reference class." Analysing an observer's experience into a sequence of "observer-moments" helps avoid certain paradoxes; but the main ambiguity is the selection of the appropriate "reference class": for Carter's WAP this might correspond to all real or potential observer-moments in our universe; for the SAP, to all in the multiverse. Bostrom's mathematical development shows that choosing either too broad or too narrow a reference class leads to counter-intuitive results, but he is not able to prescribe an ideal choice.


title: Anthropic principle

text: According to Jürgen Schmidhuber, the anthropic principle essentially just says that the conditional probability of finding yourself in a universe compatible with your existence is always 1. It does not allow for any additional nontrivial predictions such as "gravity won't change tomorrow". To gain more predictive power, additional assumptions on the prior distribution of alternative universes are necessary.


title: Anthropic principle

text: Playwright and novelist Michael Frayn describes a form of the Strong Anthropic Principle in his 2006 book "The Human Touch", which explores what he characterises as "the central oddity of the Universe":


title: Anthropic principle

text: Carter chose to focus on a tautological aspect of his ideas, which has resulted in much confusion. In fact, anthropic reasoning interests scientists because of something that is only implicit in the above formal definitions, namely that we should give serious consideration to there being other universes with different values of the "fundamental parameters"—that is, the dimensionless physical constants and initial conditions for the Big Bang. Carter and others have argued that life as we know it would not be possible in most such universes. In other words, the universe we are in is fine tuned to permit life. Collins & Hawking (1973) characterized Carter's then-unpublished big idea as the postulate that "there is not one universe but a whole infinite ensemble of universes with all possible initial conditions". If this is granted, the anthropic principle provides a plausible explanation for the fine tuning of our universe: the "typical" universe is not fine-tuned, but given enough universes, a small fraction will be capable of supporting intelligent life. Ours must be one of these, and so the observed fine tuning should be no cause for wonder.


title: Anthropic principle

text: Although philosophers have discussed related concepts for centuries, in the early 1970s the only genuine physical theory yielding a multiverse of sorts was the many-worlds interpretation of quantum mechanics. This would allow variation in initial conditions, but not in the truly fundamental constants. Since that time a number of mechanisms for producing a multiverse have been suggested: see the review by Max Tegmark. An important development in the 1980s was the combination of inflation theory with the hypothesis that some parameters are determined by symmetry breaking in the early universe, which allows parameters previously thought of as "fundamental constants" to vary over very large distances, thus eroding the distinction between Carter's weak and strong principles. At the beginning of the 21st century, the string landscape emerged as a mechanism for varying essentially all the constants, including the number of spatial dimensions.


title: Anthropic principle

text: The anthropic idea that fundamental parameters are selected from a multitude of different possibilities (each actual in some universe or other) contrasts with the traditional hope of physicists for a theory of everything having no free parameters. As Albert Einstein said: "What really interests me is whether God had any choice in the creation of the world." In 2002, some proponents of the leading candidate for a "theory of everything", string theory, proclaimed "the end of the anthropic principle" since there would be no free parameters to select. In 2003, however, Leonard Susskind stated: "...it seems plausible that the landscape is unimaginably large and diverse. Whether we like it or not, this is the kind of behavior that gives credence to the Anthropic Principle."<ref name="arXiv:hep-th/0302219"></ref>


title: Anthropic principle

text: The modern form of a design argument is put forth by intelligent design. Proponents of intelligent design often cite the fine-tuning observations that (in part) preceded the formulation of the anthropic principle by Carter as a proof of an intelligent designer. Opponents of intelligent design are not limited to those who hypothesize that other universes exist; they may also argue, anti-anthropically, that the universe is less fine-tuned than often claimed, or that accepting fine tuning as a brute fact is less astonishing than the idea of an intelligent creator. Furthermore, even accepting fine tuning, Sober (2005) and Ikeda and Jefferys, argue that the Anthropic Principle as conventionally stated actually undermines intelligent design.


title: Anthropic principle

text: Paul Davies's book "The Goldilocks Enigma" (2006) reviews the current state of the fine-tuning debate in detail, and concludes by enumerating the following responses to that debate:


title: Anthropic principle

text: Omitted here is Lee Smolin's model of cosmological natural selection, also known as "fecund universes", which proposes that universes have "offspring" that are more plentiful if they resemble our universe. Also see Gardner (2005).


title: Anthropic principle

text: Clearly each of these hypotheses resolve some aspects of the puzzle, while leaving others unanswered. Followers of Carter would admit only option 3 as an anthropic explanation, whereas 3 through 6 are covered by different versions of Barrow and Tipler's SAP (which would also include 7 if it is considered a variant of 4, as in Tipler 1994).


title: Anthropic principle

text: The anthropic principle, at least as Carter conceived it, can be applied on scales much smaller than the whole universe. For example, Carter (1983) inverted the usual line of reasoning and pointed out that when interpreting the evolutionary record, one must take into account cosmological and astrophysical considerations. With this in mind, Carter concluded that given the best estimates of the age of the universe, the evolutionary chain culminating in "Homo sapiens" probably admits only one or two low probability links.


title: Anthropic principle

text: No possible observational evidence bears on Carter's WAP, as it is merely advice to the scientist and asserts nothing debatable. The obvious test of Barrow's SAP, which says that the universe is "required" to support life, is to find evidence of life in universes other than ours. Any other universe is, by most definitions, unobservable (otherwise it would be included in "our" portion of "this" universe). Thus, in principle Barrow's SAP cannot be falsified by observing a universe in which an observer cannot exist.


title: Anthropic principle

text: Hogan has emphasised that it would be very strange if all fundamental constants were strictly determined, since this would leave us with no ready explanation for apparent fine tuning. In fact we might have to resort to something akin to Barrow and Tipler's SAP: there would be no option for such a universe "not" to support life.


title: Anthropic principle

text: The probability of observing value "X" is then proportional to "N"("X") "P"("X"). A generic feature of an analysis of this nature is that the expected values of the fundamental physical constants should not be "over-tuned", i.e. if there is some perfectly tuned predicted value (e.g. zero), the observed value need be no closer to that predicted value than what is required to make life possible. The small but finite value of the cosmological constant can be regarded as a successful prediction in this sense.


title: Anthropic principle

text: One thing that would "not" count as evidence for the Anthropic Principle is evidence that the Earth or the Solar System occupied a privileged position in the universe, in violation of the Copernican principle (for possible counterevidence to this principle, see Copernican principle), unless there was some reason to think that that position was a necessary condition for our existence as observers.


title: Anthropic principle

text: Fred Hoyle may have invoked anthropic reasoning to predict an astrophysical phenomenon. He is said to have reasoned, from the prevalence on Earth of life forms whose chemistry was based on carbon-12 nuclei, that there must be an undiscovered resonance in the carbon-12 nucleus facilitating its synthesis in stellar interiors via the triple-alpha process. He then calculated the energy of this undiscovered resonance to be 7.6 million electronvolts. Willie Fowler's research group soon found this resonance, and its measured energy was close to Hoyle's prediction.


title: Anthropic principle

text: However, in 2010 Helge Kragh argued that Hoyle did not use anthropic reasoning in making his prediction, since he made his prediction in 1953 and anthropic reasoning did not come into prominence until 1980. He called this an "anthropic myth," saying that Hoyle and others made an after-the-fact connection between carbon and life decades after the discovery of the resonance.


title: Anthropic principle

text: Don Page criticized the entire theory of cosmic inflation as follows. He emphasized that initial conditions that made possible a thermodynamic arrow of time in a universe with a Big Bang origin, must include the assumption that at the initial singularity, the entropy of the universe was low and therefore extremely improbable. Paul Davies rebutted this criticism by invoking an inflationary version of the anthropic principle. While Davies accepted the premise that the initial state of the visible universe (which filled a microscopic amount of space before inflating) had to possess a very low entropy value—due to random quantum fluctuations—to account for the observed thermodynamic arrow of time, he deemed this fact an advantage for the theory. That the tiny patch of space from which our observable universe grew had to be extremely orderly, to allow the post-inflation universe to have an arrow of time, makes it unnecessary to adopt any "ad hoc" hypotheses about the initial entropy state, hypotheses other Big Bang theories require.


title: Anthropic principle

text: String theory predicts a large number of possible universes, called the "backgrounds" or "vacua". The set of these vacua is often called the "multiverse" or "anthropic landscape" or "string landscape". Leonard Susskind has argued that the existence of a large number of vacua puts anthropic reasoning on firm ground: only universes whose properties are such as to allow observers to exist are observed, while a possibly much larger set of universes lacking such properties go unnoticed.


title: Anthropic principle

text: Steven Weinberg believes the Anthropic Principle may be appropriated by cosmologists committed to nontheism, and refers to that Principle as a "turning point" in modern science because applying it to the string landscape "may explain how the constants of nature that we observe can take values suitable for life without being fine-tuned by a benevolent creator". Others—most notably David Gross but also Lubos Motl, Peter Woit, and Lee Smolin—argue that this is not predictive. Max Tegmark, Mario Livio, and Martin Rees argue that only some aspects of a physical theory need be observable and/or testable for the theory to be accepted, and that many well-accepted theories are far from completely testable at present.


title: Anthropic principle

text: Jürgen Schmidhuber (2000–2002) points out that Ray Solomonoff's theory of universal inductive inference and its extensions already provide a framework for maximizing our confidence in any theory, given a limited sequence of physical observations, and some prior distribution on the set of possible explanations of the universe.


title: Anthropic principle

text: There are two kinds of dimensions: spatial (bidirectional) and temporal (unidirectional). Let the number of spatial dimensions be "N" and the number of temporal dimensions be "T". That "N" = 3 and "T" = 1, setting aside the compactified dimensions invoked by string theory and undetectable to date, can be explained by appealing to the physical consequences of letting "N" differ from 3 and "T" differ from 1. The argument is often of an anthropic character and possibly the first of its kind, albeit before the complete concept came into vogue.


title: Anthropic principle

text: The implicit notion that the dimensionality of the universe is special is first attributed to Gottfried Wilhelm Leibniz, who in the Discourse on Metaphysics suggested that the world is "". Immanuel Kant argued that 3-dimensional space was a consequence of the inverse square law of universal gravitation. While Kant's argument is historically important, John D. Barrow said that it "gets the punch-line back to front: it is the three-dimensionality of space that explains why we see inverse-square force laws in Nature, not vice-versa" (Barrow 2002: 204).


title: Anthropic principle

text: In 1920, Paul Ehrenfest showed that if there is only one time dimension and greater than three spatial dimensions, the orbit of a planet about its Sun cannot remain stable. The same is true of a star's orbit around the center of its galaxy. Ehrenfest also showed that if there are an even number of spatial dimensions, then the different parts of a wave impulse will travel at different speeds. If there are formula_1 spatial dimensions, where "k" is a positive whole number, then wave impulses become distorted. In 1922, Hermann Weyl showed that Maxwell's theory of electromagnetism works only with three dimensions of space and one of time. Finally, Tangherlini showed in 1963 that when there are more than three spatial dimensions, electron orbitals around nuclei cannot be stable; electrons would either fall into the nucleus or disperse.


title: Anthropic principle

text: Max Tegmark expands on the preceding argument in the following anthropic manner. If "T" differs from 1, the behavior of physical systems could not be predicted reliably from knowledge of the relevant partial differential equations. In such a universe, intelligent life capable of manipulating technology could not emerge. Moreover, if "T" > 1, Tegmark maintains that protons and electrons would be unstable and could decay into particles having greater mass than themselves. (This is not a problem if the particles have a sufficiently low temperature.) Lastly, if "N" < 3, gravitation of any kind becomes problematic, and the universe is probably too simple to contain observers. For example, when "N" < 3, nerves cannot cross without intersecting. Hence anthropic and other arguments rule out all cases except "N" = 3 and "T" = 1, which happens to describe the world around us.


title: Anthropic principle

text: On the other hand, in view of creating black holes from an ideal monatomic gas under its self-gravity, Wei-Xiang Feng showed that (3+1)-dimensional spacetime is the marginal dimensionality. Moreover, it is the unique dimensionality that can afford "stable" gas sphere with a "positive" cosmological constant. However, a self-gravitating gas cannot be stably bound if the mass sphere is larger than ~10 solar masses due to the small positiveness of the cosmological constant observed.


title: Anthropic principle

text: In 2019, James Scargill argued that complex life may be possible with two spatial dimensions. According to Scargill, a purely scalar theory of gravity may enable a local gravitational force, and 2D networks may be sufficient for complex neural networks.


title: Anthropic principle

text: Some of the metaphysical disputes and speculations include, for example, attempts to back Pierre Teilhard de Chardin's earlier interpretation of the universe as being Christ centered (compare Omega Point), expressing a "creatio evolutiva" instead the elder notion of "creatio continua". From a strictly secular, humanist perspective, it allows as well to put human beings back in the center, an anthropogenic shift in cosmology. Karl W. Giberson has laconically stated that


title: Anthropic principle

text: William Sims Bainbridge disagreed with de Chardin's optimism about a future Omega Point at the end of history, arguing that logically we are trapped at the Omicron Point, in the middle of the Greek alphabet rather than advancing to the end, because the universe does not need to have any characteristics that would support our further technical progress, if the Anthropic principle merely requires it to be suitable for our evolution to this point.


title: Anthropic principle

text: A thorough extant study of the anthropic principle is the book "The Anthropic Cosmological Principle" by John D. Barrow, a cosmologist, and Frank J. Tipler, a cosmologist and mathematical physicist. This book sets out in detail the many known anthropic coincidences and constraints, including many found by its authors. While the book is primarily a work of theoretical astrophysics, it also touches on quantum physics, chemistry, and earth science. An entire chapter argues that "Homo sapiens" is, with high probability, the only intelligent species in the Milky Way.


title: Anthropic principle

text: The book begins with an extensive review of many topics in the history of ideas the authors deem relevant to the anthropic principle, because the authors believe that principle has important antecedents in the notions of teleology and intelligent design. They discuss the writings of Fichte, Hegel, Bergson, and Alfred North Whitehead, and the Omega Point cosmology of Teilhard de Chardin. Barrow and Tipler carefully distinguish teleological reasoning from "eutaxiological" reasoning; the former asserts that order must have a consequent purpose; the latter asserts more modestly that order must have a planned cause. They attribute this important but nearly always overlooked distinction to an obscure 1883 book by L. E. Hicks.


title: Anthropic principle

text: Seeing little sense in a principle requiring intelligent life to emerge while remaining indifferent to the possibility of its eventual extinction, Barrow and Tipler propose the final anthropic principle (FAP): Intelligent information-processing must come into existence in the universe, and, once it comes into existence, it will never die out.


title: Anthropic principle

text: Barrow and Tipler submit that the FAP is both a valid physical statement and "closely connected with moral values". FAP places strong constraints on the structure of the universe, constraints developed further in Tipler's "The Physics of Immortality". One such constraint is that the universe must end in a Big Crunch, which seems unlikely in view of the tentative conclusions drawn since 1998 about dark energy, based on observations of very distant supernovas.


title: Anthropic principle

text: In his review of Barrow and Tipler, Martin Gardner ridiculed the FAP by quoting the last two sentences of their book as defining a Completely Ridiculous Anthropic Principle (CRAP):


title: Anthropic principle

text: Carter has frequently regretted his own choice of the word "anthropic", because it conveys the misleading impression that the principle involves humans specifically, rather than intelligent observers in general. Others have criticised the word "principle" as being too grandiose to describe straightforward applications of selection effects.


title: Anthropic principle

text: A common criticism of Carter's SAP is that it is an easy "deus ex machina" that discourages searches for physical explanations. To quote Penrose again: "[I]t tends to be invoked by theorists whenever they do not have a good enough theory to explain the observed facts."


title: Anthropic principle

text: Carter's SAP and Barrow and Tipler's WAP have been dismissed as truisms or trivial tautologies—that is, statements true solely by virtue of their logical form and not because a substantive claim is made and supported by observation of reality. As such, they are criticized as an elaborate way of saying, "If things were different, they would be different," which is a valid statement, but does not make a claim of some factual alternative over another.


title: Anthropic principle

text: Critics of the Barrow and Tipler SAP claim that it is neither testable nor falsifiable, and thus is not a scientific statement but rather a philosophical one. The same criticism has been leveled against the hypothesis of a multiverse, although some argue that it does make falsifiable predictions. A modified version of this criticism is that we understand so little about the emergence of life, especially intelligent life, that it is effectively impossible to calculate the number of observers in each universe. Also, the prior distribution of universes as a function of the fundamental constants is easily modified to get any desired result.


title: Anthropic principle

text: Many criticisms focus on versions of the strong anthropic principle, such as Barrow and Tipler's "anthropic cosmological principle", which are teleological notions that tend to describe the existence of life as a "necessary prerequisite" for the observable constants of physics. Similarly, Stephen Jay Gould, Michael Shermer, and others claim that the stronger versions of the anthropic principle seem to reverse known causes and effects. Gould compared the claim that the universe is fine-tuned for the benefit of our kind of life to saying that sausages were made long and narrow so that they could fit into modern hotdog buns, or saying that ships had been invented to house barnacles. These critics cite the vast physical, fossil, genetic, and other biological evidence consistent with life having been fine-tuned through natural selection to adapt to the physical and geophysical environment in which life exists. Life appears to have adapted to the universe, and not vice versa.


title: Anthropic principle

text: Some applications of the anthropic principle have been criticized as an argument by lack of imagination, for tacitly assuming that carbon compounds and water are the only possible chemistry of life (sometimes called "carbon chauvinism", see also alternative biochemistry). The range of fundamental physical constants consistent with the evolution of carbon-based life may also be wider than those who advocate a fine-tuned universe have argued. For instance, Harnik et al. propose a Weakless Universe in which the weak nuclear force is eliminated. They show that this has no significant effect on the other fundamental interactions, provided some adjustments are made in how those interactions work. However, if some of the fine-tuned details of our universe were violated, that would rule out complex structures of any kind—stars, planets, galaxies, etc.


title: Anthropic principle

text: Lee Smolin has offered a theory designed to improve on the lack of imagination that anthropic principles have been accused of. He puts forth his fecund universes theory, which assumes universes have "offspring" through the creation of black holes whose offspring universes have values of physical constants that depend on those of the mother universe.


title: Anthropic principle

text: The philosophers of cosmology John Earman, Ernan McMullin, and Jesús Mosterín contend that "in its weak version, the anthropic principle is a mere tautology, which does not allow us to explain anything or to predict anything that we did not already know. In its strong version, it is a gratuitous speculation". A further criticism by Mosterín concerns the flawed "anthropic" inference from the assumption of an infinity of worlds to the existence of one like ours:


title: George Cross

text: The George Cross (GC) is the highest award bestowed by the British government for non-operational gallantry or gallantry not in the presence of an enemy. In the British honours system, the George Cross, since its introduction in 1940, has been equal in stature to the Victoria Cross, the highest military gallantry award. It is awarded "for acts of the greatest heroism or for most conspicuous courage in circumstance of extreme danger", not in the presence of the enemy, to members of the British armed forces and to British civilians. Posthumous awards have been allowed since it was instituted. It was previously awarded to residents of Commonwealth countries (and in one case to Malta, a colony that subsequently became a Commonwealth country), most of which have since established their own honours systems and no longer recommend British honours. It may be awarded to a person of any military rank in any service and to civilians including police, emergency services and merchant seamen. Many of the awards have been personally presented by the British monarch to recipients or, in the case of posthumous awards, to next of kin. The investitures are usually held at Buckingham Palace.


title: George Cross

text: The George Cross was instituted on 24 September 1940 by King George VI. At this time, shortly after the climax of the Battle of Britain and during the third week of the Blitz, there was a strong desire to reward the many acts of civilian courage. The existing awards open to civilians were not judged suitable to meet the new situation, therefore it was decided to institute the George Cross and the George Medal to recognise civilian gallantry in the face of enemy action, and brave deeds more generally.


title: George Cross

text: The medal was designed by Percy Metcalfe. The Warrant for the GC (along with that of the George Medal), dated 24 September 1940, was published in "The London Gazette" on 31 January 1941.


title: George Cross

text: The King in his speech announcing the new award, stated that it would rank next to the Victoria Cross. This was second on the Order of Wear, much higher than the then existing awards for bravery not in the presence of the enemy, the highest being the two-class Albert Medal (AM); and the lowest being the single class Empire Gallantry Medal (EGM). In a substitution of awards unprecedented in the history of British decorations, holders of the EGM were required to exchange their insignia for the GC, most receiving their replacement GC at a formal investiture. The four honorary EGM awards to foreigners were not exchanged and could therefore continue to be worn. In 1971, surviving recipients of the Albert Medal and the Edward Medal (EM) became George Cross recipients, but unlike the EGM exchange of insignia, they had the option of retaining their original insignia. Of the 69 holders of the Albert Medal and 70 holders of the Edward Medal eligible to exchange, 49 and 59 respectively took up the option.


title: George Cross

text: The award is for civilians but also for military personnel whose actions would not normally be eligible to receive military awards, such as gallantry not in the face of the enemy. The Warrant states:


title: George Cross

text: Bars can be awarded for further acts of bravery meriting the GC, although none have yet been awarded. In common with the Victoria Cross, in undress uniform or on occasions when the medal ribbon alone is worn, a miniature replica of the cross is affixed to the centre of the ribbon, a distinction peculiar to these two premier awards for bravery. In the event of a second award, a second replica would be worn on the ribbon.


title: George Cross

text: The George Cross Committee of the Cabinet Office considers cases of military and civilian gallantry. The committee has no formal terms of reference.


title: George Cross

text: Since its inception in 1940, the GC has been awarded 416 times: 401 to men, 12 to women, and three times collectively, to the Island of Malta, the Royal Ulster Constabulary (RUC) and the National Health Service. About half the recipients have been civilians. There have been 165 original awards including those to Malta, the RUC and the NHS, including 106 made before 1947. There have been 251 exchange awards, 112 to Empire Gallantry Medal recipients, 69 to Albert Medal recipients and 70 to Edward Medal recipients. Of the 162 individuals who received original awards, 86 have been posthumous. In addition, there were five posthumous recipients of the Empire Gallantry Medal whose awards in four cases were gazetted after the start of the Second World War and whose awards were also exchanged for the GC. All the other exchange recipients were living as of the date of the decisions for the exchanges.


title: George Cross

text: The George Cross has been awarded to the island of Malta, the Royal Ulster Constabulary (RUC), and the National Health Service (NHS) of the United Kingdom.


title: George Cross

text: The GC was awarded to the island of Malta in a letter dated 15 April 1942 from King George VI to the island's Governor Lieutenant-General Sir William Dobbie:


title: George Cross

text: The cross and the messages are today in the War Museum in Fort Saint Elmo, Valletta. The fortitude of the population under sustained enemy air raids, and a naval blockade which almost saw them starved into submission, won widespread admiration in Britain and other Allied nations. Eric Grove argued on the BBC in 2017 that the George Cross was awarded as a propaganda gesture and consequently 'the island of Malta could not be allowed to fall as Singapore had done. Indeed, the North African campaign was being fought in 1942 as much to sustain Malta as vice versa.'


title: George Cross

text: The George Cross was incorporated into the Flag of Malta in 1943 and, since independence in 1964, remains on the flag.


title: George Cross

text: The GC was awarded to the RUC in 1999 by Queen Elizabeth II following the advice of the first Blair ministry. The citation published by Buckingham Palace on 23 November 1999 stated:


title: George Cross

text: The RUC was controversial before and during the Troubles; typically, Irish nationalists saw it as pro-unionist, while unionists had solidarity with the hundreds of RUC officers killed by republican paramilitaries. As part of the Northern Ireland peace process an Independent Commission on Policing for Northern Ireland produced the "Patten Report" in September 1999, which recommended structural changes and renaming the RUC the "Police Service of Northern Ireland" (PSNI). The subsequent GC award was interpreted by some as a compensation or sop to unionists and RUC supporters for accepting the substantive changes; the UK government denied this. The Queen presented the George Cross on 12 April 2000 in a ceremony at Hillsborough Castle, County Down, attended by the senior RUC officers; the cross was accepted by PC Paul Slaine, who had lost both legs in a 1992 IRA attack.


title: George Cross

text: The Police (Northern Ireland) Act 2000 gave effect to much of the Patten Report, with "the Police Service of Northern Ireland (incorporating the Royal Ulster Constabulary)" established on 4 November 2001. The pre-2001 RUC is often retrospectively referred to by sympathisers as "RUC GC"; the 2000 act established a registered charity "to be known as 'The Royal Ulster Constabulary GC Foundation' for the purpose of marking the sacrifices and honouring the achievements of the Royal Ulster Constabulary"; other instances include the names of the RUC GC Widows' Association, RUC GC Historical Society, and RUCGC–PSNI Benevolent Fund.


title: George Cross

text: On 5 July 2021, on the 73rd anniversary of the founding of the NHS of the UK, Queen Elizabeth II announced in a personal handwritten message that the four NHS organisations of the United Kingdom would be awarded the George Cross. It was reported that the award was recommended by the Prime Minister, Boris Johnson. The conferral of the award followed an 18-month period in which the health service has been at the forefront of the fight against the coronavirus pandemic in the UK.


title: George Cross

text: It is with great pleasure, on behalf of a grateful nation, that I award the George Cross to the National Health Services of the United Kingdom. This award recognises all NHS staff, past and present, across all disciplines and all four nations. Over more than seven decades, and especially in recent times, you have supported the people of our country with courage, compassion and dedication, demonstrating the highest standards of public service. You have our enduring thanks and heartfelt appreciation. Elizabeth R.


title: George Cross

text: There have been 10 GCs awarded to Canadians including those by substitution for awards superseded by the GC. The recipients comprised nine men and one woman. The GC is no longer awarded to Canadians by the King of Canada, who awards the Canadian Cross of Valour instead.


title: George Cross

text: The George Cross was awarded to 23 Australians, 11 to the Australian forces and 12 to civilians. It is the highest decoration of the Australian honours system after the British Victoria Cross and the Victoria Cross for Australia. Although Australia established the Cross of Valour within the Australian honours system in 1975 'for acts of the most conspicuous courage in circumstances of extreme peril' it was not until 1992 that Australia officially ceased recommending British honours. During the period 1975 to 1992, the last George Cross to an Australian was awarded in 1978.


title: George Cross

text: Of the 23 awards, 14 were direct awards and nine were Empire Gallantry Medal (two), Albert Medal (six) and Edward Medal (one) exchange awards. Four awards were to officers of the Royal Australian Naval Volunteer Reserve who served in the extremely dangerous role of mine disposal during the Second World War. Privates Benjamin Gower Hardy and Ralph Jones were posthumously awarded the George Cross for manning a Vickers machine gun during the Cowra breakout, a mass escape by Japanese prisoners of war in central New South Wales on 5 August 1944. Hardy and Jones disabled the weapon and denied its use to the escaping prisoners before they were overwhelmed and killed by the escapees. Courage of a different sort was displayed by two prisoners of war who endured terrible suffering. Captain Lionel Colin Matthews was eventually executed by his captors for building a resistance network in British North Borneo in the Second World War, while Private Horace William Madden, captured in Korea in 1951, died of privations while assisting fellow prisoners and openly resisting enemy efforts to force him to collaborate. The last Australian to be awarded the GC (in 1978) was Constable Michael Kenneth Pratt of the Victoria Police, Melbourne, for arresting two armed bank robbers in June 1976. For 39 years until the award to Dominic Troulon in 2017, Pratt was the most recent living civilian George Cross recipient.


title: George Cross

text: A memorial to Australian recipients, George Cross Park, was opened in Canberra, the Australian capital, on 4 April 2001 by the Governor General of Australia, Sir William Deane.


title: George Cross

text: In 1999, the New Zealand Cross replaced the role of the George Cross. Up until then, the last George Cross awarded to a New Zealander, was posthumously awarded to Sgt Stewart Guthrie of the New Zealand Police for his actions and bravery during the Aramoana massacre.


title: George Cross

text: Holders of the Victoria Cross or the George Cross are entitled to an annuity, the amount of which is determined by the awarding government. , the annuity paid by the British government was £10,000. In Canada under the "Gallantry Awards Order", members of the Canadian Forces, or people who joined the British forces before 31 March 1949 while domiciled in Canada or Newfoundland, receive $3,000 per year. Australia has been responsible for the payment of both the Victoria Cross Allowance and the George Cross annuity since the 1940s. The Victoria Cross Allowance which includes both the Victoria Cross for Australia and the British Victoria Cross is included in s.103 of the "Veterans' Entitlement Act" and is presently $A4,447 per year. Although there is not a statutory instrument for the payment of the George Cross annuity, both annuities for the Australian Cross of Valour and George Cross match the Victoria Cross Allowance payment.


title: George Cross

text: Since 1943, in accordance with the "George Cross (Restriction of Use) Ordinance", it is unlawful in Malta to use the George Cross, an imitation of it or the words "George Cross" for the purposes of trade or business without the Prime Minister's authorisation.


title: Aldosterone

text: Aldosterone is the main mineralocorticoid steroid hormone produced by the zona glomerulosa of the adrenal cortex in the adrenal gland. It is essential for sodium conservation in the kidney, salivary glands, sweat glands, and colon. It plays a central role in the homeostatic regulation of blood pressure, plasma sodium (Na), and potassium (K) levels. It does so primarily by acting on the mineralocorticoid receptors in the distal tubules and collecting ducts of the nephron. It influences the reabsorption of sodium and excretion of potassium (from and into the tubular fluids, respectively) of the kidney, thereby indirectly influencing water retention or loss, blood pressure, and blood volume. When dysregulated, aldosterone is pathogenic and contributes to the development and progression of cardiovascular and kidney disease. Aldosterone has exactly the opposite function of the atrial natriuretic hormone secreted by the heart.


title: Aldosterone

text: Aldosterone is part of the renin–angiotensin–aldosterone system. It has a plasma half-life of less than 20 minutes. Drugs that interfere with the secretion or action of aldosterone are in use as antihypertensives, like lisinopril, which lowers blood pressure by blocking the angiotensin-converting enzyme (ACE), leading to lower aldosterone secretion. The net effect of these drugs is to reduce sodium and water retention but increase retention of potassium. In other words, these drugs stimulate the excretion of sodium and water in urine, while they block the excretion of potassium.


title: Aldosterone

text: Another example is spironolactone, a potassium-sparing diuretic of the steroidal spirolactone group, which interferes with the aldosterone receptor (among others) leading to lower blood pressure by the mechanism described above.


title: Aldosterone

text: Aldosterone was first isolated by Sylvia Tait (Simpson) and Jim Tait in 1953; in collaboration with Tadeusz Reichstein.


title: Aldosterone

text: The corticosteroids are synthesized from cholesterol within the zona glomerulosa and zona fasciculata of adrenal cortex. Most steroidogenic reactions are catalysed by enzymes of the cytochrome P450 family. They are located within the mitochondria and require adrenodoxin as a cofactor (except 21-hydroxylase and 17α-hydroxylase).


title: Aldosterone

text: Aldosterone and corticosterone share the first part of their biosynthetic pathways. The last parts are mediated either by the aldosterone synthase (for aldosterone) or by the 11β-hydroxylase (for corticosterone). These enzymes are nearly identical (they share 11β-hydroxylation and 18-hydroxylation functions), but aldosterone synthase is also able to perform an 18-oxidation. Moreover, aldosterone synthase is found within the zona glomerulosa at the outer edge of the adrenal cortex; 11β-hydroxylase is found in the zona glomerulosa and zona fasciculata.


title: Aldosterone

text: Aldosterone is the primary of several endogenous members of the class of mineralocorticoids in humans. Deoxycorticosterone is another important member of this class. Aldosterone tends to promote Na and water retention, and lower plasma K concentration by the following mechanisms:


title: Aldosterone

text: Aldosterone is responsible for the reabsorption of about 2% of filtered sodium in the kidneys, which is nearly equal to the entire sodium content in human blood under normal glomerular filtration rates.


title: Aldosterone

text: Aldosterone, probably acting through mineralocorticoid receptors, may positively influence neurogenesis in the dentate gyrus.


title: Aldosterone

text: Steroid receptors are intracellular. The aldosterone mineralocorticoid receptor (MR) complex binds on the DNA to specific hormone response element, which leads to gene specific transcription.


title: Aldosterone

text: Some of the transcribed genes are crucial for transepithelial sodium transport, including the three subunits of the epithelial sodium channel (ENaC), the Na/K pumps and their regulatory proteins serum and glucocorticoid-induced kinase, and channel-inducing factor, respectively.


title: Aldosterone

text: The MR is stimulated by both aldosterone and cortisol, but a mechanism protects the body from excess aldosterone receptor stimulation by glucocorticoids (such as cortisol), which happen to be present at much higher concentrations than mineralocorticoids in the healthy individual. The mechanism consists of an enzyme called 11 β-hydroxysteroid dehydrogenase (11β-HSD). This enzyme co-localizes with intracellular adrenal steroid receptors and converts cortisol into cortisone, a relatively inactive metabolite with little affinity for the MR. Liquorice, which contains glycyrrhetinic acid, can inhibit 11β-HSD and lead to a mineralocorticoid excess syndrome.


title: Aldosterone

text: Angiotensin is involved in regulating aldosterone and is the core regulation. Angiotensin II acts synergistically with potassium, and the potassium feedback is virtually inoperative when no angiotensin II is present. A small portion of the regulation resulting from angiotensin II must take place indirectly from decreased blood flow through the liver due to constriction of capillaries. When the blood flow decreases so does the destruction of aldosterone by liver enzymes.


title: Aldosterone

text: Although sustained production of aldosterone requires persistent calcium entry through low-voltage-activated Ca channels, isolated zona glomerulosa cells are considered nonexcitable, with recorded membrane voltages that are too hyperpolarized to permit Ca channels entry. However, mouse zona glomerulosa cells within adrenal slices spontaneously generate membrane potential oscillations of low periodicity; this innate electrical excitability of zona glomerulosa cells provides a platform for the production of a recurrent Ca channels signal that can be controlled by angiotensin II and extracellular potassium, the 2 major regulators of aldosterone production. Voltage-gated Ca channels have been detected in the zona glomerulosa of the human adrenal, which suggests that Ca channel blockers may directly influence the adrenocortical biosynthesis of aldosterone in vivo.


title: Aldosterone

text: The amount of plasma renin secreted is an indirect function of the serum potassium as probably determined by sensors in the carotid artery.


title: Aldosterone

text: Adrenocorticotropic hormone (ACTH), a pituitary peptide, also has some stimulating effect on aldosterone, probably by stimulating the formation of deoxycorticosterone, a precursor of aldosterone. Aldosterone is increased by blood loss, pregnancy, and possibly by further circumstances such as physical exertion, endotoxin shock, and burns.


title: Aldosterone

text: The aldosterone production is also affected to one extent or another by nervous control, which integrates the inverse of carotid artery pressure, pain, posture, and probably emotion (anxiety, fear, and hostility) (including surgical stress). Anxiety increases aldosterone, which must have evolved because of the time delay involved in migration of aldosterone into the cell nucleus. Thus, there is an advantage to an animal's anticipating a future need from interaction with a predator, since too high a serum content of potassium has very adverse effects on nervous transmission.


title: Aldosterone

text: Pressure-sensitive baroreceptors are found in the vessel walls of nearly all large arteries in the thorax and neck, but are particularly plentiful in the sinuses of the carotid arteries and in the arch of the aorta. These specialized receptors are sensitive to changes in mean arterial pressure. An increase in sensed pressure results in an increased rate of firing by the baroreceptors and a negative feedback response, lowering systemic arterial pressure. Aldosterone release causes sodium and water retention, which causes increased blood volume, and a subsequent increase in blood pressure, which is sensed by the baroreceptors. To maintain normal homeostasis these receptors also detect low blood pressure or low blood volume, causing aldosterone to be released. This results in sodium retention in the kidney, leading to water retention and increased blood volume.


title: Aldosterone

text: Aldosterone levels vary as an inverse function of sodium intake as sensed via osmotic pressure. The slope of the response of aldosterone to serum potassium is almost independent of sodium intake. Aldosterone is increased at low sodium intakes, but the rate of increase of plasma aldosterone as potassium rises in the serum is not much lower at high sodium intakes than it is at low. Thus, potassium is strongly regulated at all sodium intakes by aldosterone when the supply of potassium is adequate, which it usually is in "primitive" diets.


title: Aldosterone

text: Feedback by aldosterone concentration itself is of a nonmorphological character (that is, other than changes in the cells' number or structure) and is poor, so the electrolyte feedbacks predominate, short term.


title: Aldosterone

text: Hyperaldosteronism is abnormally increased levels of aldosterone, while hypoaldosteronism is abnormally decreased levels of aldosterone.


title: Aldosterone

text: A measurement of aldosterone in blood may be termed a "plasma aldosterone concentration" ("PAC"), which may be compared to plasma renin activity (PRA) as an aldosterone-to-renin ratio.


title: Aldosterone

text: Primary aldosteronism, also known as "primary hyperaldosteronism", is characterized by the overproduction of aldosterone by the adrenal glands, when not a result of excessive renin secretion. It leads to arterial hypertension (high blood pressure) associated with hypokalemia, usually a diagnostic clue. Secondary hyperaldosteronism, on the other hand, is due to overactivity of the renin–angiotensin system.


title: Aldosterone

text: Depending on cause and other factors, hyperaldosteronism can be treated by surgery and/or medically, such as by aldosterone antagonists.


title: Aldosterone

text: The ratio of renin to aldosterone is an effective screening test to screen for primary hyperaldosteronism related to adrenal adenomas. It is the most sensitive serum blood test to differentiate primary from secondary causes of hyperaldosteronism. Blood obtained when the patient has been standing for more than 2 hours are more sensitive than those from when the patient is lying down. Before the test, individuals should not restrict salt and low potassium should be corrected before the test because it can suppress aldosterone secretion.


title: Aldosterone

text: An ACTH stimulation test for aldosterone can help in determining the cause of hypoaldosteronism, with a low aldosterone response indicating a primary hypoaldosteronism of the adrenals, while a large response indicating a secondary hypoaldosteronism.


title: Aldosterone

text: The most common cause of this condition (and related symptoms) is Addison's disease; it is typically treated by fludrocortisone, which has a much longer persistence (1 day) in the bloodstream.


title: American and British English spelling differences

text: Despite the various English dialects spoken from country to country and within different regions of the same country, there are only slight regional variations in English orthography, the two most notable variations being British and American spelling. Many of the differences between American and British English date back to a time before spelling standards were developed. For instance, some spellings seen as "American" today were once commonly used in Britain, and some spellings seen as "British" were once commonly used in the United States.


text: A "British standard" began to emerge following the 1755 publication of Samuel Johnson's "A Dictionary of the English Language", and an "American standard" started following the work of Noah Webster and, in particular, his "An American Dictionary of the English Language", first published in 1828. Webster's efforts at spelling reform were somewhat effective in his native country, resulting in certain well-known patterns of spelling differences between the American and British varieties of English. However, English-language spelling reform has rarely been adopted otherwise. As a result, modern English orthography varies only minimally between countries and is far from phonemic in any country.


text: In the early 18th century, English spelling was inconsistent. These differences became noticeable after the publishing of influential dictionaries. Today's British English spellings mostly follow Johnson's "A Dictionary of the English Language" (1755), while many American English spellings follow Webster's "An American Dictionary of the English Language" ("ADEL", "Webster's Dictionary", 1828).


text: Webster was a proponent of English spelling reform for reasons both philological and nationalistic. In "A Companion to the American Revolution" (2008), John Algeo notes: "it is often assumed that characteristically American spellings were invented by Noah Webster. He was very influential in popularizing certain spellings in America, but he did not originate them. Rather [...] he chose already existing options such as "center, color" and "check" for the simplicity, analogy or etymology". William Shakespeare's first folios, for example, used spellings such as "center" and "color" as much as "centre" and "colour". Webster did attempt to introduce some reformed spellings, as did the Simplified Spelling Board in the early 20th century, but most were not adopted. In Britain, the influence of those who preferred the Norman (or Anglo-French) spellings of words proved to be decisive. Later spelling adjustments in the United Kingdom had little effect on today's American spellings and vice versa.


text: For the most part, the spelling systems of most Commonwealth countries and Ireland closely resemble the British system. In Canada, the spelling system can be said to follow both British and American forms, and Canadians are somewhat more tolerant of foreign spellings when compared with other English-speaking nationalities. Australian spelling mostly follows British spelling norms but has strayed slightly, with some American spellings incorporated as standard. New Zealand spelling is almost identical to British spelling, except in the word "fiord" (instead of "fjord"). There is an increasing use of macrons in words that originated in Māori and an unambiguous preference for "-ise" endings (see below).


text: Most words ending in an unstressed "-our" in British English (e.g., ) end in "-or" in American English (). Wherever the vowel is unreduced in pronunciation (e.g., "contour", "paramour", "troubadour", and "velour"), the spelling is uniform everywhere.


text: Most words of this kind came from Latin, where the ending was spelled "-or". They were first adopted into English from early Old French, and the ending was spelled "-our", "-or" or "-ur". After the Norman conquest of England, the ending became "-our" to match the later Old French spelling. The "-our" ending was used not only in new English borrowings, but was also applied to the earlier borrowings that had used "-or". However, "-or" was still sometimes found. The first three folios of Shakespeare's plays used both spellings before they were standardised to "-our" in the Fourth Folio of 1685. After the Renaissance, new borrowings from Latin were taken up with their original "-or" ending, and many words once ending in "-our" (for example, "chancellour" and "governour") reverted to "-or". Many words of the "-our/or" group do not have a Latin counterpart that ends in "-or"; for example, "armo(u)r", "behavio(u)r", "harbo(u)r", "neighbo(u)r"; also "arbo(u)r", meaning "shelter", though senses "tree" and "tool" are always "arbor", a false cognate of the other word. Some 16th- and early 17th-century British scholars indeed insisted that "-or" be used for words from Latin (e.g., "") and "-our" for French loans; but in many cases the etymology was not clear, and therefore some scholars advocated "-or" only and others "-our" only.


text: Webster's 1828 dictionary had only "-or" and is given much of the credit for the adoption of this form in the United States. By contrast, Johnson's 1755 (pre-U.S. independence and establishment) dictionary used "-our" for all words still so spelled in Britain (like "colour"), but also for words where the "u" has since been dropped: "ambassadour", "emperour", "governour", "inferiour", "perturbatour", "superiour"; "errour", "horrour", "mirrour", "tenour", "terrour", "tremour". Johnson, unlike Webster, was not an advocate of spelling reform, but chose the spelling best derived, as he saw it, from among the variations in his sources. He preferred French over Latin spellings because, as he put it, "the French generally supplied us". English speakers who moved to America took these preferences with them. In the early 20th century, H. L. Mencken notes that "' appears in the 1776 Declaration of Independence, but it seems to have been put there rather by accident than by design". In Jefferson's original draft it is spelled "honour". In Britain, examples of rarely appear in Old Bailey court records from the 17th and 18th centuries, whereas there are thousands of examples of their "-our" counterparts. One notable exception is '. ' and ' were equally frequent in Britain until the 17th century; "honor" only exists in the UK now as the spelling of "Honor Oak", a district of London and the occasional given name Honor.


text: In derivatives and inflected forms of the "-our/or" words, British usage depends on the nature of the suffix used. The "u" is kept before English suffixes that are freely attachable to English words (for example in ) and suffixes of Greek or Latin origin that have been adopted into English (for example in ). However, before Latin suffixes that are not freely attachable to English words, the "u":


text: In American usage, derivatives and inflected forms are built by simply adding the suffix in all cases (for example, ', ' etc.) since the "u" is absent to begin with.


text: American usage, in most cases, keeps the "u" in the word "glamour", which comes from Scots, not Latin or French. ' is sometimes used in imitation of the spelling reform of other "-our" words to "-or". Nevertheless, the adjective "glamorous" often drops the first "u". ' is a somewhat common variant of ' in the US. The British spelling is very common for ' (and "") in the formal language of wedding invitations in the US. The name of the has a "u" in it because the spacecraft was named after British Captain James Cook's ship, . The (former) special car on Amtrak's "Coast Starlight" train is known as the Pacific Parlour car, not "Pacific Parlor". Proper names such as "Pearl Harbor" or "Sydney Harbour" are usually spelled according to their native-variety spelling vocabulary.


text: The name of the herb "savory" is spelled thus everywhere, although the related adjective "savo(u)ry", like "savo(u)r", has a "u" in the UK. "Honor" (the name) and "arbor" (the tool) have "-or" in Britain, as mentioned above, as does the word "pallor". As a general noun, "rigour" has a "u" in the UK; the medical term "rigor" (sometimes ) does not, such as in "rigor mortis", which is Latin. Derivations of "rigour"/"rigor" such as "rigorous", however, are typically spelled without a "u", even in the UK. Words with the ending "-irior", "-erior" or similar are spelled thus everywhere.


text: The word "armour" was once somewhat common in American usage but has disappeared except in some brand names such as Under Armour.


text: The agentive suffix "-or" ("separator", "elevator", "translator", "animator", etc.) is spelled thus both in American and British English.


text: Commonwealth countries normally follow British usage. Canadian English most commonly uses the "-our" ending and "-our-" in derivatives and inflected forms. However, owing to the close historic, economic, and cultural relationship with the United States, "-or" endings are also sometimes used. Throughout the late 19th and early to mid-20th century, most Canadian newspapers chose to use the American usage of "-or" endings, originally to save time and money in the era of manual movable type. However, in the 1990s, the majority of Canadian newspapers officially updated their spelling policies to the British usage of "-our". This coincided with a renewed interest in Canadian English, and the release of the updated "Gage Canadian Dictionary" in 1997 and the first "Canadian Oxford Dictionary" in 1998. Historically, most libraries and educational institutions in Canada have supported the use of the "Oxford English Dictionary" rather than the American "Webster's Dictionary". Today, the use of a distinctive set of Canadian English spellings is viewed by many Canadians as one of the unique aspects of Canadian culture (especially when compared to the United States).


text: In Australia, "-or" endings enjoyed some use throughout the 19th century and in the early 20th century. Like Canada, though, most major Australian newspapers have switched from ""-or"" endings to ""-our"" endings. The ""-our"" spelling is taught in schools nationwide as part of the Australian curriculum. The most notable countrywide use of the "-or" ending is for one of the country's major political parties, the , which was originally called "the Australian Labour Party" (name adopted in 1908), but was frequently referred to as both "Labour" and "Labor". The "Labor" was adopted from 1912 onward due to the influence of the and King O'Malley. On top of that, some place names in South Australia such as Victor Harbor, Franklin Harbor or Outer Harbor are usually spelled with the -or spellings. Aside from that, "-our" is now almost universal in Australia but the "-or" endings remain a minority variant. New Zealand English, while sharing some words and syntax with Australian English, follows British usage.


text: In British English, some words from French, Latin or Greek end with a consonant followed by an unstressed "-re" (pronounced ). In modern American English, most of these words have the ending "-er". The difference is most common for words ending "-bre" or "-tre": British spellings all have "-er" in American spelling.


text: In Britain, both "-re" and "-er" spellings were common before Johnson's 1755 dictionary was published. Following this, "-re" became the most common usage in Britain. In the United States, following the publication of "Webster's Dictionary" in the early 19th century, American English became more standardized, exclusively using the "-er" spelling.


text: In addition, spelling of some words have been changed from "-re" to "-er" in both varieties. These include "chapter", "December", "disaster", "enter", "filter", "letter", "member", "minister", "monster", "November", "number", "October", "offer", "oyster", "powder", "proper", "September", "sober" and "tender". Words using the ""-meter"" suffix (from Ancient Greek -μέτρον "métron", via French "-mètre") normally had the "-re" spelling from earliest use in English but were superseded by "-er". Examples include "thermometer" and "barometer".


text: The "e" preceding the "r" is kept in American-inflected forms of nouns and verbs, for example, , which are respectively in British English. According to the "OED", "" is a ""word ... of 3 syllables (in careful pronunciation)"" (i.e., ), yet there is no vowel in the spelling corresponding to the second syllable (). The OED third edition (revised entry of June 2016) allows either two or three syllables. On the Oxford Dictionaries Online website, the three-syllable version is listed only as the American pronunciation of "centering". The "e" is dropped for other derivations, for example, "central", "fibrous", "spectral". But, the existence of related words without "e" before the "r" is not proof for the existence of an "-re" British spelling: for example, "entry" and "entrance" come from "enter", which has not been spelled "entre" for centuries.


text: The difference relates only to root words; "-er" rather than "-re" is universal as a suffix for agentive ("reader", "user", "winner") and comparative ("louder", "nicer") forms. One outcome is the British distinction of "meter" for a measuring instrument from "" for the unit of length. But, while "" is often spelled as "-re", pentameter, hexameter, etc. are always "-er".


text: Many other words have "-er" in British English. These include Germanic words, such as "anger", "mother", "timber" and "water", and such Romance-derived words as "danger", "quarter" and "river".


text: The ending "-cre", as in "acre",<ref name="acre/louvre">Although "acre" was spelled "æcer" in Old English and "aker" in Middle English, the "acre" spelling of Middle French was introduced in the 15th century. Similarly, "loover" was respelled in the 17th century by influence of the unrelated Louvre. (See "OED", s.v. "acre" and "louvre")</ref> "lucre", "massacre", and "mediocre", is used in both British and American English to show that the "c" is pronounced rather than . The spellings "euchre" and "ogre" are also the same in both British and American English.


text: "Fire" and its associated adjective "fiery" are the same in both British and American English, although the noun was spelled "fier" in Old and Middle English.


text: In the United States, the spelling "theatre" is sometimes used when referring to the art form of theatre, while the building itself, as noted above, generally is spelled "theater". For example, the University of Wisconsin–Madison has a "Department of "Theatre" and Drama", which offers courses that lead to the "Bachelor of Arts in "Theatre"", and whose professed aim is "to prepare our graduate students for successful 21st Century careers in the "theatre" both as practitioners and scholars".


text: Some placenames in the United States use "Centre" in their names. Examples include the Stonebriar Centre mall, the cities of Rockville Centre and Centreville, Centre County and Centre College. Sometimes, these places were named before spelling changes but more often the spelling serves as an affectation. Proper names are usually spelled according to their native-variety spelling vocabulary; so, for instance, although "Peter" is the usual form of the male given name, as a surname both the spellings "Peter" and "Petre" (the latter notably borne by a British lord) are found.


text: For British "", the American practice varies: the "Merriam-Webster Dictionary" prefers the "-re" spelling, but "The American Heritage Dictionary of the English Language" prefers the "-er" spelling.


text: More recent French loanwords keep the "-re" spelling in American English. These are not exceptions when a French-style pronunciation is used ( rather than ), as with "double entendre", "genre" and "oeuvre". However, the unstressed pronunciation of an "-er" ending is used with some words, including "cadre", "macabre", "maître d'", Notre Dame, "piastre", and "timbre".


text: The "-re" endings are mostly standard throughout the Commonwealth. The "-er" spellings are recognized as minor variants in Canada, partly due to United States influence. They are sometimes used in proper names (such as Toronto's controversially named Centerpoint Mall).


text: For "advice"/"advise" and "device"/"devise", American English and British English both keep the noun–verb distinction both graphically and phonetically (where the pronunciation is - for the noun and - for the verb). For "licence/license" or "practice/practise", British English also keeps the noun–verb distinction graphically (although phonetically the two words in each pair are homophones with - pronunciation). On the other hand, American English uses "license" and "practice" for both nouns and verbs (with - pronunciation in both cases too).


text: American English has kept the Anglo-French spelling for "defense" and "offense", which are "defence" and "offence" in British English. Likewise, there are the American "pretense" and British "pretence"; but derivatives such as "defensive", "offensive", and "pretension" are always thus spelled in both systems.


text: The spelling "connexion" is now rare in everyday British usage, its use lessening as knowledge of Latin attenuates, and it has never been used in the US: the more common "connection" has become the standard worldwide. According to the "Oxford English Dictionary" the older spelling is more etymologically conservative, since the original Latin word had "-xio-". The American usage comes from Webster, who abandoned "-xion" and preferred "-ction". "Connexion" was still the house style of "The Times" of London until the 1980s and was still used by Post Office Telecommunications for its telephone services in the 1970s, but had by then been overtaken by "connection" in regular usage (for example, in more popular newspapers). "Connexion" (and its derivatives "connexional" and "connexionalism") is still in use by the Methodist Church of Great Britain to refer to the whole church as opposed to its constituent districts, circuits and local churches, whereas the US-majority United Methodist Church uses "Connection".


text: "Complexion" (which comes from "complex") is standard worldwide and "complection" is rare. However, the adjective "complected" (as in "dark-complected"), although sometimes proscribed, is on equal ground in the US with "complexioned." It is not used in this way in the UK, although there exists a rare alternative meaning of "complicated".


text: In some cases, words with "old-fashioned" spellings are retained widely in the US for historical reasons (cf. connexionalism).


text: Many words, especially medical words, that are written with "ae/æ" or "oe/œ" in British English are written with just an "e" in American English. The sounds in question are or (or, unstressed, , or ). Examples (with non-American letter in bold): "aeon", "anaemia", "anaesthesia", "caecum", "caesium", "coeliac", "diarrhoea", "encyclopaedia", "faeces", "foetal", "gynaecology", "haemoglobin", "haemophilia", "leukaemia", "oesophagus", "oestrogen", "orthopaedic", "palaeontology", "paediatric", "paedophile". "Oenology" is acceptable in American English but is deemed a minor variant of "enology", whereas although "archeology" and "ameba" exist in American English, the British versions "amoeba" and "archaeology" are more common. The chemical "haem" (named as a shortening of "haemoglobin") is spelled "heme" in American English, to avoid confusion with "hem".


text: Canadian English mostly follows American English in this respect, although it is split on "gynecology" (e.g. Society of Obstetricians and Gynaecologists of Canada vs. the Canadian Medical Association's Canadian specialty profile of "Obstetrics/gynecology"). "Pediatrician" is preferred roughly 10 to 1 over "paediatrician", while "foetal" and "oestrogen" are similarly uncommon.


text: Words that can be spelled either way in American English include "aesthetics" and "archaeology" (which usually prevail over "esthetics" and "archeology"), as well as "palaestra", for which the simplified form "palestra" is described by Merriam-Webster as "chiefly Brit[ish]."


text: Words that can be spelled either way in British English include "chamaeleon", "encyclopaedia", "homoeopathy", "mediaeval" (a minor variant in both AmE and BrE), "foetid" and "foetus". The spellings "foetus" and "foetal" are Britishisms based on a mistaken etymology. The etymologically correct original spelling "fetus" reflects the Latin original and is the standard spelling in medical journals worldwide; the Oxford English Dictionary notes that "In Latin manuscripts both "fētus" and "foetus" are used".


text: <αι> and <οι>, which are diphthongs in Ancient Greek, were transliterated into Latin as <ae> and <oe>. The ligatures æ and œ were introduced when the sounds became monophthongs, and later applied to words not of Greek origin, in both Latin (for example, "cœli") and French (for example, "œuvre"). In English, which has adopted words from all three languages, it is now usual to replace "Æ/æ" with "Ae/ae" and "Œ/œ" with "Oe/oe". In many words, the digraph has been reduced to a lone "e" in all varieties of English: for example, oeconomics", "praemium", and aenigma". In others, it is kept in all varieties: for example, "phoenix", and usually "subpoena", but Phenix in Virginia. This is especially true of names: "Aegean" (the sea), "Caesar", "Oedipus", "Phoebe", etc. There is no reduction of Latin -ae plurals (e.g., "larvae"); nor where the digraph <ae>/<oe> does not result from the Greek-style ligature: for example, "maelstrom", "toe". The British form "aeroplane" is an instance (compare other "aero-" words such as "aerosol"). The now chiefly North American "airplane" is not a respelling but a recoining, modelled after "airship" and "aircraft". The word "airplane" dates from 1907, at which time the prefix "aero-" was trisyllabic, often written "aëro-".


text: In Canada, "e" is generally preferred over "oe" and often over "ae", but "oe" and "ae" are sometimes found in academic and scientific writing as well as government publications (for example the fee schedule of the Ontario Health Insurance Plan) and some words such as "palaeontology" or "aeon". In Australia, it can go either way such being "medieval" is spelt with the "e" rather than "ae", as with American usage along with numerous other words such as "eon" or "fetus", while other words such as "oestrogen" or "paediatrician" go the British way. The "Macquarie Dictionary" also notes a growing tendency towards replacing "ae" and "oe" with "e" worldwide and with the exception of manoeuvre, all British or American spellings are acceptable variants. Elsewhere, the British usage prevails, but the spellings with just "e" are increasingly used. "Manoeuvre" is the only spelling in Australia, and the most common one in Canada, where "maneuver" and "manoeuver" are also sometimes found.


text: The "-ize" spelling is often incorrectly seen as an Americanism in Britain. It has been in use since the 15th century, predating the "-ise" spelling by over a century. The verb-forming suffix "-ize" comes directly from Ancient Greek () or Late Latin , while "-ise" comes via French . The "Oxford English Dictionary" () recommends "-ize" and lists the "-ise" form as an alternative.


text: Publications by Oxford University Press (OUP)—such as Henry Watson Fowler's "A Dictionary of Modern English Usage", "Hart's Rules", and "The Oxford Guide to English Usage"—also recommend "-ize". However, Robert Allan's "Pocket Fowler's Modern English Usage" considers either spelling to be acceptable anywhere but the U.S.


text: British spelling mostly uses "-ise" ("organise", "realise", "recognise"), though "-ize" is sometimes used. The ratio between "-ise" and "-ize" stood at 3:2 in the British National Corpus up to 2002. The spelling "-ise" is more commonly used in UK mass media and newspapers, including "The Times" (which switched conventions in 1992), "The Daily Telegraph", "The Economist" and the BBC. The Government of the United Kingdom additionally uses "-ise", stating "do not use Americanisms" justifying that the spelling "is often seen as such". The "-ize" form is known as Oxford spelling and is used in publications of the Oxford University Press, most notably the "Oxford English Dictionary", and of other academic publishers such as "Nature", the "Biochemical Journal" and "The Times Literary Supplement". It can be identified using the IETF language tag en-GB-oxendict (or, historically, by en-GB-oed).


text: In Ireland, India, Australia, and New Zealand "-ise" spellings strongly prevail: the "-ise" form is preferred in Australian English at a ratio of about 3:1 according to the "Macquarie Dictionary".


text: In Canada, the "-ize" ending is more common, although the "Ontario Public School Spelling Book" spelt most words in the "-ize" form, but allowed for duality with a page insert as late as the 1970s, noting: though the "-ize" spelling was in fact the convention used in the "OED", that a choice to spell such words in the "-ise" form was "a matter of personal preference", however a "pupil" having made the decision, one way or the other, thereafter ought to write uniformly not only for a given word, but to apply that same uniformity consistently for all words where the option is found. Just as with "-yze" spellings, however, in Canada the "ize" form remains the preferred or more common spelling, though both can still be found, yet the "-ise" variation, once more common amongst older Canadians, is increasingly employed less often in favour of the "-ize" spelling. (The alternate convention offered as a matter of choice may have been due to the fact that although there were an increasing number of American and British based dictionaries with Canadian Editions by the late 1970s, these were largely only supplemental in terms of vocabulary with subsequent definitions. It wasn't until the mid-1990s that Canadian based dictionaries became increasingly common.)


text: Worldwide, "-ize" endings prevail in scientific writing and are commonly used by many international organizations, such as United Nations Organizations (such as the World Health Organization and the International Civil Aviation Organization) and the International Organization for Standardization (but not by the Organisation for Economic Co-operation and Development). The European Union's style guides require the usage of -"ise". Proofreaders at the EU's Publications Office ensure consistent spelling in official publications such as the "Official Journal of the European Union" (where legislation and other official documents are published), but the "-ize" spelling may be found in other documents.


text: The same applies to inflections and derivations such as "colonised"/"colonized" and "modernisation"/"modernization".


text: The ending "-yse" is British and "-yze" is American. Thus, in British English "analyse", "catalyse", "hydrolyse" and "paralyse", but in American English "analyze", "catalyze", "hydrolyze" and "paralyze".


text: "Analyse" was the more common spelling in 17th- and 18th-century English. Some dictionaries of the time however preferred "analyze", such as John Kersey's of 1702, Nathan Bailey's of 1721 and Samuel Johnson's of 1755. In Canada, "-yze" is preferred, but "-yse" is also very common. In South Africa, Australia and New Zealand, "-yse" is the prevailing form.


text: English verbs ending in either "-lyse" or "-lyze" are not similar to the original Greek verb, which is "λύω lýo" ("I release"). Instead, they come from the noun form "lysis", with the "-ise" or "-ize" suffix. For example, "analyse" comes from French "analyser", formed by haplology from the French "analysiser", which would be spelled "analysise" or "analysize" in English.


text: "Hart's Rules for Compositors and Readers at the University Press, Oxford" states: "In verbs such as analyse, catalyse, paralyse, "-lys-" is part of the Greek stem (corresponding to the element "-lusis") and not a suffix like "-ize". The spelling "-yze" is therefore etymologically incorrect, and must not be used, unless American printing style is being followed."


text: British and other Commonwealth English use the ending "-logue" while American English commonly uses the ending "-log" for words like "analog(ue)", "catalog(ue)", "dialog(ue)", "homolog(ue)", etc. The "-gue" spelling, as in "catalogue", is used in the US, but "catalog" is more common. In contrast, "dialogue", "epilogue", "prologue", and "monologue" are extremely common spellings compared to "dialog" etc. in American English, although both forms are treated as acceptable ways to spell the words (thus the inflected forms, "cataloged" and "cataloging" vs. "catalogued" and "cataloguing"). Words such as "demagogue", "pedagogue", "synagogue" are seldom used without "-ue" even in American English.


text: In Australia, "analog" is standard for the adjective, but both "analogue" and "analog" are current for the noun; in all other cases the "-gue" endings strongly prevail, for example "monologue", except for such expressions as "dialog box" in computing, which are also used in other Commonwealth countries. In Australia, "analog" is used in its technical and electronic sense, as in "analog electronics". In Canada and New Zealand, "analogue" is used, but "analog" has some currency as a technical term (e.g., in electronics, as in "analog electronics" as opposed to "digital electronics" and some video-game consoles might have an "analog stick"). The "-ue" is absent worldwide in related words like "analogy", "analogous", and "analogist".


text: Both British and American English use the spelling "-gue" with a silent "-ue" for certain words that are not part of the "-ogue" set, such as "tongue" (cf. tong), "plague", "vague", and "league." In addition, when the "-ue" is not silent, as in the words "argue," "ague" and "segue," all varieties of English use "-gue."


text: The plural of the noun "bus" is usually "buses", with "busses" a minor American variant. Conversely, inflections of the verb "bus" usually double the "s" in British ("busses, bussed, bussing") but not American ("buses, bused, busing"). In Australia, both are common, with the American slightly more common.


text: The final consonant of an English word is sometimes doubled in both American and British spelling when adding a suffix beginning with a vowel, for example "strip/stripped", which prevents confusion with "stripe/striped" and shows the difference in pronunciation (see digraph). Generally, this happens only when the word's final syllable is stressed and when it also ends with a lone vowel followed by a lone consonant. In British English, however, a final "-l" is often doubled even when the final syllable is unstressed. This exception is no longer usual in American English, seemingly because of Noah Webster. The "-ll-" spellings are nevertheless still deemed acceptable variants by both Merriam-Webster Collegiate and American Heritage dictionaries.


text: Among consonants other than "l", practice varies for some words, such as where the final syllable has secondary stress or an unreduced vowel. In the United States, the spellings "kidnaped" and "worshiped", which were introduced by the "Chicago Tribune" in the 1920s, are common, but "kidnapped" and "worshipped" prevail. "Kidnapped" and "worshipped" are the only standard British spellings. However, "focused" is the predominant spelling in both British and American English, "focussed" being just a minor variant in British English.


text: Conversely, there are words where British writers prefer a single "l" and Americans a double "l". In American usage, the spelling of words is usually not changed when they form the main part (not prefix or suffix) of other words, especially in newly formed words and in words whose main part is in common use. Words with this spelling difference include


text: "appall", "enrollment", "fulfill", "fulfillment", "installment", "skillful", "thralldom", "willful". These words have monosyllabic cognates always written with "-ll": "pall", "roll", "fill", "stall", "skill", "thrall", "will". Cases where a single "l" nevertheless occurs in both American and British English include "null"→"annul", "annulment"; "till"→"until" (although some prefer "til" to reflect the single "l" in "until", sometimes using a leading apostrophe ("til"); this should be considered a hypercorrection as "till" predates the use of "until"); and others where the connection is not clear or the monosyllabic cognate is not in common use in American English (e.g., "null" is used mainly as a technical term in law, mathematics, and computer science).


text: In the UK, a single "l" is generally preferred in American forms "distill", "instill", "enroll", and "enthrallment", and "enthrall", although "ll" was formerly used; these are always spelled with "ll" in American usage. The former British spellings "dulness", "instal", and "fulness" are now quite rare. The Scottish "tolbooth" is cognate with "tollbooth", but it has a distinct meaning.


text: In both American and British usages, words normally spelled "-ll" usually drop the second "l" when used as prefixes or suffixes, for example "all"→"almighty", "altogether"; "full"→"handful", "useful"; "well"→"welcome", "welfare"; "chill"→"chilblain".


text: Both the British "fulfil" and the American "fulfill" never use "-ll-" in the middle (i.e., *"fullfill" and *"fullfil" are incorrect).


text: Johnson wavered on this issue. His dictionary of 1755 lemmatizes "distil" and "instill", "downhil" and "uphill".


text: British English sometimes keeps a silent "e" when adding suffixes where American English does not. Generally speaking, British English drops it in only some cases in which it is needed to show pronunciation whereas American English only uses it where needed.


text: Both forms of English keep the silent "e" in the words "dyeing", "singeing", and "swingeing" (in the sense of "dye", "singe", and "swinge"), to distinguish from "dying", "singing", "swinging" (in the sense of "die", "sing", and "swing"). In contrast, the verb "bathe" and the British verb "bath" both form "bathing". Both forms of English vary for "tinge" and "twinge"; both prefer "cringing", "hinging", "lunging", "syringing".


text: A "c" is generally soft when followed by an "e", "i", or "y". One word with a pronunciation that is an exception in British English, "sceptic", is spelled "skeptic" in American English. See "Miscellaneous spelling differences" below.


text: In a few cases, essentially the same word has a different spelling that reflects a different pronunciation.


text: As well as the miscellaneous cases listed in the following table, the past tenses of some irregular verbs differ in both spelling and pronunciation, as with "smelt" (UK) versus "smelled" (US) (see American and British English grammatical differences: Verb morphology).


text: In the UK, Ireland, Australia, New Zealand and Canada, it is more common to end some past tense verbs with a "t" as in "learnt" or "dreamt" rather than "learned" or "dreamed". However, such spellings are also found in American English. However, in American English, "burned" and "burnt" have different usages.


text: British English often prefers hyphenated compounds, such as "anti-smoking", whereas American English discourages the use of hyphens in compounds where there is no compelling reason, so "antismoking" is much more common. Many dictionaries do not point out such differences. Canadian and Australian usage is mixed, although Commonwealth writers generally hyphenate compounds of the form noun plus phrase (such as "editor-in-chief"). Commander-in-chief prevails in all forms of English.


text: Acronyms pronounced as words are often written in title case by Commonwealth writers, but usually as upper case by Americans: for example, "Nasa / NASA" or "Unicef / UNICEF". This does not apply to abbreviations that are pronounced as individual letters (referred to by some as "initialisms"), such as "US", "IBM", or "PRC" (the People's Republic of China), which are virtually always written as upper case. However, sometimes title case is still used in the UK, such as "Pc" (Police Constable).


text: Contractions where the final letter is present are often written in British English without full stops/periods ("Mr", "Mrs", "Dr", "St", "Ave"). Abbreviations where the final letter is not present generally do take full stops/periods (such as "vol.", "etc.", "i.e.", "ed."); British English shares this convention with the French: "Mlle", "Mme", "Dr", "Ste", but "M." for "Monsieur". In American and Canadian English, abbreviations like "St.", "Ave.", "Mr.", "Mrs.", "Ms.", "Dr.", and "Jr.", usually require full stops/periods. Some initials are usually upper case in the US but lower case in the UK: liter/litre and its compounds ("2 L" or "25 mL" vs "2 l" or "25 ml"); and ante meridiem and post meridiem ("10 P.M." or "10 PM" vs "10 p.m." or "10 pm"). Both "AM/PM" and "a.m./p.m." are acceptable in American English, but U.S. style guides overwhelmingly prefer "a.m./p.m."


text: The use of quotation marks, also called inverted commas or speech marks, is complicated by the fact that there are two kinds: single quotation marks (') and double quotation marks ("). British usage, at one stage in the recent past, preferred single quotation marks for ordinary use, but double quotation marks are again now increasingly common; American usage has always preferred double quotation marks, as have Canadian, Australian, and New Zealand English. It is the practice to alternate the type of quotation marks used where there is a quotation within a quotation.


text: The convention used to be, and in American English still is, to put full stops (periods) and commas inside the quotation marks, irrespective of the sense. British style now prefers to punctuate according to the sense, in which punctuation marks only appear inside quotation marks if they were there in the original. Formal British English practice requires a full stop to be put inside the quotation marks if the quoted item is a full sentence that ends where the main sentence ends, but it is common to see the stop outside the ending quotation marks.


title: Political corruption

text: Political corruption is the use of powers by government officials or their network contacts for illegitimate private gain.


title: Political corruption

text: Forms of corruption vary, but can include bribery, lobbying, extortion, cronyism, nepotism, parochialism, patronage, influence peddling, graft, and embezzlement. Corruption may facilitate criminal enterprise such as drug trafficking, money laundering, and human trafficking, though it is not restricted to these activities. Misuse of government power for other purposes, such as repression of political opponents and general police brutality, is also considered political corruption.


title: Political corruption

text: Over time, corruption has been defined differently. For example, in a simple context, while performing work for a government or as a representative, it is unethical to accept a gift. Any free gift could be construed as a scheme to lure the recipient towards some biases. In most cases, the gift is seen as an intention to seek certain favors such as work promotion, tipping in order to win a contract, job or exemption from certain tasks in the case of junior worker handing in the gift to a senior employee who can be key in winning the favor.


title: Political corruption

text: Some forms of corruption – now called "institutional corruption" – are distinguished from bribery and other kinds of obvious personal gain. A similar problem of corruption arises in any institution that depends on financial support from people who have interests that may conflict with the primary purpose of the institution.


title: Political corruption

text: An illegal act by an officeholder constitutes political corruption only if the act is directly related to their official duties, is done under color of law or involves trading in influence. The activities that constitute illegal corruption differ depending on the country or jurisdiction. For instance, some political funding practices that are legal in one place may be illegal in another. In some cases, government officials have broad or ill-defined powers, which make it difficult to distinguish between legal and illegal actions.


title: Political corruption

text: Worldwide, bribery alone is estimated to involve over 1 trillion US dollars annually. A state of unrestrained political corruption is known as a kleptocracy, literally meaning "rule by thieves".