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Wednesday, November 17, 2010

Cloud computing

Cloud computing is Web-based processing, whereby shared resources, software, and information are provided to computers and other devices (such as smartphones) on demand over the Internet.

Cloud computing is a natural evolution of the widespread adoption of virtualization, Service-oriented architecture and utility computing. Details are abstracted from consumers, who no longer have need for expertise in, or control over, the technology infrastructure "in the cloud" that supports them. Cloud computing describes a new supplement, consumption, and delivery model for IT services based on the Internet, and it typically involves over-the-Internet provision of dynamically scalable and often virtualized resources. It is a byproduct and consequence of the ease-of-access to remote computing sites provided by the Internet. This frequently takes the form of web-based tools or applications that users can access and use through a web browser as if it were a program installed locally on their own computer. NIST provides a somewhat more objective and specific definition here. The term "cloud" is used as a metaphor for the Internet, based on the cloud drawing used in the past to represent the telephone network, and later to depict the Internet in computer network diagrams as an abstraction of the underlying infrastructure it represents. Typical cloud computing providers deliver common business applications online that are accessed from another Web service or software like a Web browser, while the software and data are stored on servers.


Gadget

A gadget is a small technological object (such as a device or an appliance) that has a particular function, but is often thought of as a novelty. Gadgets are invariably considered to be more unusually or cleverly designed than normal technological objects at the time of their invention. Gadgets are sometimes also referred to as gizmos.

History

  

The origins of the word "gadget" trace back to the 19th century. According to the Oxford English Dictionary, there is anecdotal evidence for the use of "gadget" as a placeholder name for a technical item whose precise name one can't remember since the 1850s; with Robert Brown's 1886 book Spunyarn and Spindrift, A sailor boy’s log of a voyage out and home in a China tea-clipper containing the earliest known usage in print. The etymology of the word is disputed. A widely circulated story holds that the word gadget was "invented" when Gaget, Gauthier & Cie, the company behind the repoussé construction of the Statue of Liberty (1886), made a small-scale version of the monument and named it after their firm; however this contradicts the evidence that the word was already used before in nautical circles, and the fact that it did not become popular, at least in the USA, until after World War I. Other sources cite a derivation from the French gâchette which has been applied to various pieces of a firing mechanism, or the French gagée, a small tool or accessory.

The October 1918 issue of Notes and Queries contains a multi-article entry on the word "gadget" (12 S. iv. 187). H. Tapley-Soper of The City Library, Exeter, writes:

    A discussion arose at the Plymouth meeting of the Devonshire Association in 1916 when it was suggested that this word should be recorded in the list of local verbal provincialisms. Several members dissented from its inclusion on the ground that it is in common use throughout the country; and a naval officer who was present said that it has for years been a popular expression in the service for a tool or implement, the exact name of which is unknown or has for the moment been forgotten. I have also frequently heard it applied by motor-cycle friends to the collection of fitments to be seen on motor cycles. 'His handle-bars are smothered in gadgets' refers to such things as speedometers, mirrors, levers, badges, mascots, &c., attached to the steering handles. The 'jigger' or short-rest used in billiards is also often called a 'gadget'; and the name has been applied by local platelayers to the 'gauge' used to test the accuracy of their work. In fact, to borrow from present-day Army slang, 'gadget' is applied to 'any old thing.'

The usage of the term in military parlance extended beyond the navy. In the book "Above the Battle" by Vivian Drake, published in 1918 by D. Appleton & Co., of New York and London, being the memoirs of a pilot in the British Royal Flying Corps, there is the following passage: "Our ennui was occasionally relieved by new gadgets -- "gadget" is the Flying Corps slang for invention! Some gadgets were good, some comic and some extraordinary."

By the second half of the twentieth century, the term "gadget" had taken on the connotations of compactness and mobility. In the 1965 essay "The Great Gizmo" (a term used interchangeably with "gadget" throughout the essay), the architectural and design critic Reyner Banham defines the item as:

    A characteristic class of US products––perhaps the most characteristic––is a small self-contained unit of high performance in relation to its size and cost, whose function is to transform some undifferentiated set of circumstances to a condition nearer human desires. The minimum of skills is required in its installation and use, and it is independent of any physical or social infrastructure beyond that by which it may be ordered from catalogue and delivered to its prospective user. A class of servants to human needs, these clip-on devices, these portable gadgets, have coloured American thought and action far more deeply––I suspect––than is commonly understood.

Today, the term has gained widespread currency in a variety of industries and activities. It can refer to tools and toys as diverse as "smartphones", GPS navigation devices, key finders, USB toys, and radio controlled cars.

 Other uses

The first atomic bomb was nicknamed the gadget by the scientists of the Manhattan Project, tested at the Trinity site.
 Application gadgets
In the software industry, "gadget" refers to computer programs that provide services without needing an independent application to be launched for each one, but instead run in an environment that manages multiple gadgets. There are several implementations based on existing software development techniques, like JavaScript, form input, and various image formats.

    Further information: Google Desktop, Google Gadgets, Microsoft Gadgets, and Dashboard software Apple Widgets

The earliest documented use of the term gadget in context of software engineering was in 1985 by the developers of AmigaOS, the operating system of the Amiga computers (intuition.library and also later gadtools.library). It denotes what other technological traditions call GUI widget—a control element in graphical user interface. This naming convention remains in continuing use (as of 2008) since then.
It is not known whether other software companies are explicitly drawing on that inspiration when featuring the word in names of their technologies or simply referring to the generic meaning. The word widget is older in this context.

List of computer science fields

Computer science has a number of major sub-fields which can be classified by a number of means (for example the ACM classification system).

Algorithms
    formal processes used for computation, and the efficiency of these processes
Applications
    design and development software for everyday use
Artificial intelligence
    implementation and study of systems that exhibit (either behaviourally or seemingly) an autonomous intelligence or behaviour of their own, sometimes inspired by the characteristics of living beings. Computer science is closely tied with AI, as software and computers are primary tools for the development and progression of artificial intelligence
Compilers
    ways of efficiently translating algorithms from one form (usually a programming language) to another
Computational complexity theory
    fundamental bounds (esp. time and storage space) on computations
Computer programming
    the act of writing algorithms in a programming language
Computer graphics
    algorithms both for generating visual images synthetically and for integrating or altering visual and spatial information sampled from the real world
Computer vision
    the science and technology of machines that see. As a scientific discipline, computer vision is concerned with the theory behind artificial systems that extract information from images (aimed to perform as good as humans do).
Cryptography
    algorithms for protecting private data, including encryption
Data mining
    the process of sorting through large amounts of data and picking out relevant information.; closely related to information retrieval
Data structures
    the organization and storage of data
Networking
    algorithms and protocols for reliably communicating data across long distances, often including error correction
Operating systems
    systems for managing computer programs and data structures
Programming languages
    formal languages for expressing algorithms and the properties of these languages
Robotics
    algorithms for controlling the behavior of robots
Scientific computing
    algorithms for use in the sciences, especially (but not exclusively) biology (as in bioinformatics), physics, and chemistry
Software engineering
    the process of designing, developing, and testing programs
Steganography
    algorithms for covertly hiding data in seemingly unrelated documents, such as graphics
Type Theory
    formal analysis of the types of data, and the use of these types to understand properties of programs, especially program safety

Galaxy

A galaxy is a massive, gravitationally bound system that consists of stars and stellar remnants, an interstellar medium of gas dust, and an important but poorly understood component tentatively dubbed dark matter. The name is from the Greek root galaxias [γαλαξίας], literally meaning "milky", a reference to the Milky Way galaxy. Typical galaxies range from dwarfs with as few as ten million (107) stars, up to giants with a hundred trillion (1014) stars, all orbiting the galaxy's center of mass. Galaxies may contain many star systems, star clusters, and various interstellar clouds. The Sun is one of the stars in the Milky Way galaxy; the Solar System includes the Earth and all the other objects that orbit the Sun.

Historically, galaxies have been categorized according to their apparent shape (usually referred to as their visual morphology). A common form is the elliptical galaxy, which has an ellipse-shaped light profile. Spiral galaxies are disk-shaped assemblages with dusty, curving arms. Galaxies with irregular or unusual shapes are known as irregular galaxies, and typically result from disruption by the gravitational pull of neighboring galaxies. Such interactions between nearby galaxies, which may ultimately result in galaxies merging, may induce episodes of significantly increased star formation, producing what is called a starburst galaxy. Small galaxies that lack a coherent structure could also be referred to as irregular galaxies.

There are probably more than 170 billion (1.7 × 1011) galaxies in the observable universe. Most galaxies are 1,000 to 100,000 parsecs in diameter and are usually separated by distances on the order of millions of parsecs (or megaparsecs). Intergalactic space (the space between galaxies) is filled with a tenuous gas of an average density less than one atom per cubic meter. The majority of galaxies are organized into a hierarchy of associations called clusters, which, in turn, can form larger groups called superclusters. These larger structures are generally arranged into sheets and filaments, which surround immense voids in the universe.
Although it is not yet well understood, dark matter appears to account for around 90% of the mass of most galaxies. Observational data suggests that supermassive black holes may exist at the center of many, if not all, galaxies. They are proposed to be the primary cause of active galactic nuclei found at the core of some galaxies. The Milky Way galaxy appears to harbor at least one such object within its nucleus


Etymology

 The word galaxy derives from the Greek term for our own galaxy, galaxias (γαλαξίας), or kyklos galaktikos, meaning "milky circle" for its appearance in the sky. In Greek mythology, Zeus places his son born by a mortal woman, the infant Heracles, on Hera's breast while she is asleep so that the baby will drink her divine milk and will thus become immortal. Hera wakes up while breastfeeding and then realizes she is nursing an unknown baby: she pushes the baby away and a jet of her milk sprays the night sky, producing the faint band of light known as the Milky Way.

In the astronomical literature, the capitalized word 'Galaxy' is used to refer to our galaxy, the Milky Way, to distinguish it from the billions of other galaxies. The term Milky Way first appeared in the English language in a poem by Chaucer.

    "See yonder, lo, the Galaxyë
     Which men clepeth the Milky Wey,
     For hit is whyt."
    —Geoffrey Chaucer. The House of Fame, c. 1380.

When William Herschel constructed his catalog of deep sky objects, he used the name spiral nebula for certain objects such as M31. These would later be recognized as immense conglomerations of stars, when the true distance to these objects began to be appreciated, and they would be termed island universes. However, the word Universe was understood to mean the entirety of existence, so this expression fell into disuse and the objects instead became known as galaxies.

Astrology

Astrology is a group of systems, traditions, and beliefs which hold that the relative positions of celestial bodies and related details can provide information about personality, human affairs and other "earthly" matters. A practitioner of astrology is called an astrologer. Few astrologers believe that the movements and positions of celestial bodies either directly influence life on Earth or correspond to events experienced on a human scale.[] More common is the idea that astrology is a symbolic language, an art form, or a form of divination. Despite differences in definitions, a common assumption of astrologers is that celestial placements can aid in the interpretation of past and present events, and in the prediction of the future.

Astrology is considered a pseudoscience or superstition by the scientific community, which sees a lack of statistically significant astrological predictions, while psychology explains much of the continued faith in astrology as a matter of cognitive biases. 2006 the U.S. National Science Board published a statement which said it considers belief in ten survey items, astrology among them, to be "pseudoscientific".

Numerous traditions and applications employing astrological concepts have arisen since its earliest recorded beginnings in the 3rd millennium BC. Astrology has played an important role in the shaping of culture, early astronomy, the Vedas, and various disciplines throughout history. In fact, astrology and astronomy were often regarded as synonyms before the modern era, with the desire for predictive and divinatory knowledge one of the motivating factors for astronomical observation. Astronomy began to diverge from astrology after a period of gradual separation from the Renaissance up until the 18th century. Eventually, astronomy distinguished itself as the empirical study of astronomical objects and phenomena, without regard to the terrestrial implications of astrology.

The word "astrology" comes from the Latin term astrologia ("astronomy"), which in turn derives from the Greek noun αστρολογία: ἄστρον, astron ("constellation" or "star") and -λογία, -logia ("the study of"). The word "starcraft" has also traditionally been used to mean astrology.

Core beliefs

The core beliefs of astrology were prevalent in parts of the ancient world and are epitomized in the Hermetic maxim, "as above, so below". Tycho Brahe used a similar phrase to summarize his studies in astrology: suspiciendo despicio, "by looking up I see downward". Although the principle that events in the heavens are mirrored by those on Earth was once generally held in most traditions of astrology around the world, in the West there has historically been a debate among astrologers over the nature of the mechanism behind astrology.

Although the connection between celestial mechanics and terrestrial dynamics was explored first by Isaac Newton with his development of a universal theory of gravitation, claims that the gravitational effects of the celestial bodies are what accounts for astrological generalizations are not substantiated by scientific research.

Most astrological traditions are based on the relative positions and movements of various real or construed celestial bodies and on the construction of implied or calculated celestial patterns as seen at the time and place of the event being studied. These are chiefly the astrological planets, the stars, the lunar nodes, Arabic parts and hypothetical planets. The frame of reference for such apparent positions is defined by the tropical or sidereal zodiac of twelve signs on one hand, and by the local horizon (ascendant-descendant axis) and midheaven-imum coeli axis on the other. This latter (local) frame is typically further divided into the twelve astrological houses. Furthermore, the astrological aspects are used to determine the geometric/angular relationship(s) between the various celestial bodies and angles in the horoscope.

Predictive astrology, in the Western tradition, employs two main methods: astrological transits and astrological progressions. In astrological transits the ongoing movements of the planets are interpreted for their significance as they transit through space and the horoscope. In astrological progressions the horoscope is progressed forward in time according to set methods. In Vedic astrology, the focus is on planetary periods to infer the trend, while transits are used to time significant events. Most Western astrologers no longer try to forecast actual events, but focus instead on general trends and developments. By comparison, Vedic astrologers predict both trends and events. Skeptics respond that this practice of western astrologers allows them to avoid making verifiable predictions, and gives them the ability to attach significance to arbitrary and unrelated events, in a way that suits their purpose.

In the past, astrologers often relied on close observation of celestial objects and the charting of their movements. Modern astrologers use data provided by astronomers which are transformed to a set of astrological tables called ephemerides, showing the changing zodiacal positions of the heavenly bodies through time.

Traditions

There are many traditions of astrology, some of which share similar features due to the transmission of astrological doctrines between cultures. Other traditions developed in isolation and hold different doctrines, though they too share some features due to drawing on similar astronomical sources.

 Current traditions

The main traditions used by modern astrologers are Hindu Astrology (Jyotiṣa), Western astrology, and Chinese astrology.

Vedic and Western astrology share a common ancestry as horoscopic systems of astrology, in that both traditions focus on the casting of an astrological chart or horoscope, a representation of celestial entities, for an event based on the position of the Sun, Moon, and planets at the moment of the event. However, Vedic astrology uses the sidereal or fixed or constellational zodiac, linking the signs of the zodiac to their original constellations, while Western astrology uses the tropical or seasonal zodiac. Because of the precession of the equinoxes whose cycle is ~25,686 years long, during which the extensions of the polar axes describe circles, the twelve zodiacal signs in Western astrology no longer correspond to the same part of the sky as their original constellations, due to centuries of change. In effect, in Western astrology the link between sign and constellation was broken in approximately 222 AD, whereas in Vedic astrology the constellations remain of paramount importance. Other differences between the two traditions include the use of 27 (or 28) nakshatras or lunar mansions, each 13⅓ degrees wide, which have been used in India since Vedic times, and the systems of planetary periods known as dashas.

In Chinese astrology, a quite different tradition has evolved. By contrast to Western and Indian astrology, the twelve signs of the zodiac do not divide the sky, but rather the celestial equator. The Chinese evolved a system in which each sign corresponds to one of twelve "double-hours" that govern the day, and to one of the twelve months. Each sign of the zodiac governs a different year, and combines with a system based on the five elements of Chinese cosmology to give a 60 (12 × 5) year cycle. The term Chinese astrology is used here for convenience, but it must be noted that versions of the same tradition exist in Korea, Japan, Vietnam, Thailand and other Asian countries. It appears that this is a remnant of a more ancient system of Jupiterian astrology, an astrological system primarily based on the motion of Jupiter, which orbits the Sun every 11.89 years.

Western astrology has been the result of the knowledge of the earlier Indian/Vedic and Egyptian schools (each developed in their own right, and neither shows traces of the later Babylonian influences) being diluted and simplified in passing first through Persia/Babylon, and then through Greece, and later Europe. In modern times, these traditions have come into closer contact with each other, notably with Indian and Chinese astrology having spread in more direct form to the West, while awareness of the modern notions of Western astrology is still fairly limited in Asia, and is not considered useful. Astrology in the Western world has diversified among some in modern times. New movements have appeared that have jettisoned much of more recent traditional astrology to concentrate on different approaches, such as a greater emphasis on midpoints, or a more psychological approach. Some recent Western developments include modern tropical and sidereal horoscopic astrology, including constellational and star or point-based astrology (including aspects to the fundamental planetary dynamics, such as perihelions and aphelions, and nodal points resulting from the inclinations of the planets' revolutionary planes to the Earth's ecliptic plane); heliocentric astrology, cosmobiology; psychological astrology; sun sign astrology; the Hamburg School of Astrology; and Uranian astrology, a subset of the Hamburg School.

Esoteric traditions

 Horoscopic astrology

Horoscopic astrology is a system that some claim to have developed in the Mediterranean region and specifically Hellenistic Egypt around the late 2nd or early 1st century BC. However, horoscopic astrology has been practiced in India since ancient times, and Vedic astrology is the oldest surviving form of horoscopic astrology in the world. The tradition deals with two-dimensional diagrams of the heavens, or horoscopes, created for specific moments in time. The diagram is then used to interpret the inherent meaning underlying the alignment of celestial bodies at that moment based on a specific set of rules and guidelines. A horoscope was calculated normally for the moment of an individual's birth, or at the beginning of an enterprise or event, because the alignments of the heavens at that moment were thought to determine the nature of the subject in question. One of the defining characteristics of this form of astrology that makes it distinct from other traditions is the computation of the degree of the Eastern horizon rising against the backdrop of the ecliptic at the specific moment under examination, otherwise known as the ascendant. Horoscopic astrology is the most influential and widespread form of astrology in Africa, India, Europe and the Middle East. Medieval and most modern Western traditions of astrology have Hellenistic origins.

 Horoscope

18th century Icelandic manuscript showing astrological houses and glyphs for planets and signs.
Central to horoscopic astrology and its branches is the calculation of the horoscope or astrological chart. This two-dimensional diagrammatic representation shows the celestial bodies' apparent positions in the heavens from the vantage of a location on Earth at a given time and place. The horoscope is also divided into twelve different celestial houses which govern different areas of life. Calculations performed in casting a horoscope involve arithmetic and simple geometry which serve to locate the apparent position of heavenly bodies on desired dates and times based on astronomical tables. In ancient Hellenistic astrology the ascendant demarcated the first celestial house of a horoscope. The word for the ascendant in Greek was ὡροσκόπος (hōroskopos) from which horoscope derives. In modern times, the word has come to refer to the astrological chart as a whole.

 Branches

Traditions of horoscopic astrology can be divided into four branches that are each directed towards specific subjects or purposes. Often these branches use a unique set of techniques, or a different application of the core principles of the system to a different area. Many other subsets and applications of astrology are derived from these four fundamental branches.
Natal astrology is the study of a person's natal chart to gain information about the individual and their life experience. Katarchic astrology includes both electional and event astrology. The former uses astrology to determine the most auspicious moment to begin an enterprise or undertaking, and the latter to understand everything about an event from the time at which it took place. Horary astrology is used to answer a specific question by studying the chart of the moment the question is posed to an astrologer. Mundane or world astrology is the application of astrology to world events, including weather, earthquakes, and the rise and fall of empires or religions. This includes the Astrological Ages, such as the Age of Aquarius, Age of Pisces, and so on. Each age is about 2,150 years in length, and many people use these massive ages to characterize and describe major historical ages, as well as current developments in the world.

 History

15th century image from the Très Riches Heures du Duc de Berry showing projected correlations between areas of the body and the zodiacal signs.
Many believe that the origins of much of the astrological doctrine and method that would later develop in Asia, Europe, and the Middle East are found among the ancient Babylonians and their system of celestial omens that began to be compiled around the middle of the 2nd millennium BC. They believe this system of celestial omens later spread, either directly or indirectly through the Babylonians and Assyrians, to other areas such as the Middle East, and Greece, where it merged with pre-existing indigenous forms of astrology. Thus, Babylonian astrology migrated to Greece, initially as early as the middle of the 4th century BC, and then around the late 2nd or early 1st century BC, after the Alexandrian conquests, this Babylonian astrology was mixed with the Egyptian tradition of decanic astrology to create horoscopic astrology. This new form of astrology, which appears to have originated in Alexandrian Egypt, spread across the ancient world into Europe, the Middle East, and India with varying degrees of influence.

 Before the modern era

Hand-colored version of the anonymous Flammarion woodcut (1888).
The differentiation between astronomy and astrology varied from place to place; they were strongly linked in ancient India, ancient Babylonia and medieval Europe, but separated to an extent in the Hellenistic world. The first semantic distinction between astrology and astronomy was probably given by Isidore of Seville (see astrology and astronomy).
The pattern of astronomical knowledge gained from astrological endeavors has been historically repeated across numerous cultures, from ancient India through the classical Maya civilization to medieval Europe. Given this historical contribution, astrology has been called a protoscience along with disciplines such as alchemy.
Astrology was not without criticism before the modern era; it was often challenged by Hellenistic skeptics, church authorities, and medieval Muslim astronomers, such as Al-Farabi (Alpharabius), Ibn al-Haytham (Alhazen), Abū Rayhān al-Bīrūnī, Avicenna and Averroes. Their reasons for refuting astrology were often due to both scientific (the methods used by astrologers being conjectural rather than empirical) and religious (conflicts with orthodox Islamic scholars) reasons. Ibn Qayyim Al-Jawziyya (1292–1350), in his Miftah Dar al-SaCadah, used empirical arguments in astronomy in order to refute astrology and divination.
Many prominent thinkers, philosophers and scientists, such as Galen, Paracelsus, Girolamo Cardan, Nicolaus Copernicus, Taqi al-Din, Tycho Brahe, Galileo Galilei, Johannes Kepler, Carl Jung and others, practiced or significantly contributed to astrology.

 Contemporary changes

Several innovations have occurred in contemporary astrological practice.

 Western

During the middle of the 20th century, Alfred Witte and, following him, Reinhold Ebertin pioneered the use of midpoints (see Midpoint (astrology)) in horoscopic analysis. From the 1930s to the 1980s, astrologers including Dane Rudhyar, Liz Greene and Stephen Arroyo pioneered the use of astrology for psychological analysis, with some following the lead of psychologists like Carl Jung. In the 1930s, Don Neroman developed and popularized in Europe a form of Locational Astrology under the name of "Astrogeography". In the 1970s, American astrologer Jim Lewis developed and popularized a different approach under the name of Astrocartography. Both methods purport to identify varying life conditions through differences in location.

 Vedic (Hindu astrology)

Indian astrology uses a different zodiac than Western astrology and is a branch of Vedic science. In India, there is a long-established widespread belief in astrology, and it is commonly used for daily life, foremost with regard to marriages, and secondarily with regard to career and electional and karmic astrology. In the 1960s, H.R. Seshadri Iyer, introduced a system including the concepts of yogi and avayogi. It generated interest with research oriented astrologers in the West. From the early 1990s, Indian vedic astrologer and author, V.K. Choudhry has created and developed the Systems' Approach for Interpreting Horoscopes, a simplified system of Jyotish (predictive astrology) The system, also known as "SA", helps those who are trying to learn Jyotisha. The late K.S. Krishnamurti developed the Krishnamurti Paddhati system based on the analysis of the stars (nakshatras), by sub-dividing the stars in the ratio of the dasha of the concerned planets. The system is also known as "KP" and "sub theory". In 2001, Indian scientists and politicians debated and critiqued a proposal to use state money to fund research into Vedic astrology.

Effects on world culture

Belief in astrology holds firm today in many parts of the world: in one poll, 31% of Americans expressed a belief in astrology and, according to another study, 39% considered it scientific.
Astrology has had an influence on both language and literature. For example, influenza, from medieval Latin influentia meaning influence, was so named because doctors once believed epidemics to be caused by unfavorable planetary and stellar influences. The word "disaster" comes from the Italian disastro, derived from the negative prefix dis- and from Latin aster "star", thus meaning "ill-starred". Adjectives "lunatic" (Luna/Moon), "mercurial" (Mercury), "venereal" (Venus), "martial" (Mars), "jovial" (Jupiter/Jove), and "saturnine" (Saturn) are all old words used to describe personal qualities said to resemble or be highly influenced by the astrological characteristics of the planet, some of which are derived from the attributes of the ancient Roman gods they are named after. In literature, many writers, notably Geoffrey Chaucer and William Shakespeare, used astrological symbolism to add subtlety and nuance to the description of their characters' motivation(s). More recently, Michael Ward has proposed that C.S. Lewis imbued his Chronicles of Narnia with the characteristics and symbols of the seven heavens. Often, an understanding of astrological symbolism is needed to fully appreciate such literature.

Astrology and science

Pseudoscientific concepts

Claims
Measurable correlations can be reliably found between the position of the planets and personality and human events.
Related scientific disciplines
Astronomy, Psychology
Year proposed
antiquity
Original proponents
ancient priests and astrologers
Subsequent proponents
Philip Berg, Michel Gauquelin, Linda Goodman, Liz Greene, Alan Leo, Sydney Omarr, Joan Quigley, Jackie Stallone, Athena Starwoman, Shelley von Strunckel, Richard Tarnas
In the Islamic world astrology was rejected during the turn of the 2nd millennium AD owing to the development of the scientific method and the work of al-Farabi, Alhacen, al-Biruni, Avicenna and Averroes, who made a semantic distinction between astronomy and astrology and helped to render astrology obsolete for Muslims. Muslim views on astrology have generally remained negative.
By the time of Francis Bacon and the scientific revolution, newly emerging scientific disciplines acquired a method of systematic empirical induction based upon experimental observations. At this point, astrology and astronomy began to diverge; astronomy became regarded as one of the empirical sciences, while astrology came to be understood as a part of scholastic metaphysics, and was increasingly viewed as an occult science or superstition by natural scientists. For example, Christiaan Huygens wrote in his Cosmotheoros: "And as for the Judicial Astrology, that pretends to foretel what is to come, it is such a ridiculous, and oftentimes mischievous Folly, that I do not think it fit to be so much as named." This separation accelerated through the 18th and 19th centuries.
Contemporary scientists, such as Richard Dawkins and Stephen Hawking, regard astrology as unscientific, and those such as Andrew Fraknoi of the Astronomical Society of the Pacific have labeled it a pseudoscience. In 1975, the American Humanist Association characterized those who have faith in astrology as doing so "in spite of the fact that there is no verified scientific basis for their beliefs, and indeed that there is strong evidence to the contrary".Astronomer Carl Sagan was unwilling to sign the statement, not because he felt astrology was valid, but because he found the statement's tone authoritarian. Sagan stated that he would instead have been willing to sign a statement describing and refuting the principal tenets of astrological belief, which he believed would have been more persuasive and would have produced less controversy than the circulated statement.
Astrophysicist Neil deGrasse Tyson asserted that "astrology was discredited 600 years ago with the birth of modern science. 'To teach it as though you are contributing to the fundamental knowledge of an informed electorate is astonishing in this, the 21st century'. Education should be about knowing how to think, 'And part of knowing how to think is knowing how the laws of nature shape the world around us. Without that knowledge, without that capacity to think, you can easily become a victim of people who seek to take advantage of you'".
Although astrology has not been considered a science for some time, it has been the subject of considerable research by astrologers since the beginning of the 20th century. In their study of 20th-century research into natal astrology, Geoffrey Dean, a former astrologer who became critical of the field, and coauthors documented this burgeoning research activity performed primarily within the astrological community.[57]

Research

The Mars effect: relative frequency of the diurnal position of Mars in the birth chart of "eminent athletes"[clarification needed] (after Michel Gauquelin 1991
Studies have repeatedly failed to demonstrate statistically significant relationships between astrological predictions and operationally defined outcomes. Effect size tests of astrology-based hypotheses conclude that the mean accuracy of astrological predictions is no greater than what is expected by chance. For example, when testing for cognitive, behavioral, physical and other variables, one study of 2000 astrological "time twins" born within minutes of each other did not show a celestial influence on human characteristics. It has been suggested that other statistical research is often wrongly seen as evidence for astrology due to uncontrolled artifacts.
Experimental psychologists have suggested that several different psychological phenomena can contribute to perception of astrological accuracy. One, related to confirmation bias, is that people who are given a set of multiple predictions tend to remember more of the accurate predictions ("hits") than the inaccurate ones ("misses"). Consequently, people tend to recall the set of predictions as being more accurate than it actually was. When astrological predictions turn out to correspond with some phenomena but not with others, the recollected integrity of these predictions may stem in part from this phenomenon. A second, called the Forer effect, is that individuals tend to give high accuracy ratings to descriptions of their personality that are presented to them as tailored specifically for them, but which are in fact vague and general enough to apply to a wide range of people. When predictions use vague language, the appearance that they are specific to the individual may be partially attributable to the Forer effect.
The French psychologist and statistician who devoted his life to the attempt to demonstrate the validity of certain fundamentals of astrology, Michel Gauquelin, wrote that he had found correlations between some planetary positions and certain human traits such as vocations. Gauquelin's most widely known concept is the Mars effect, which denotes a correlation between the planet Mars occupying certain positions in the sky more often at the birth of eminent sports champions than at the birth of ordinary people. A similar idea is explored by Richard Tarnas in his work Cosmos and Psyche, in which he examines correspondences between planetary alignments and historically significant events and individuals. Since its original publication in 1955, the Mars effect has been the subject of critical studies and skeptical publications which aim to refute it, and of studies in fringe journals used to support or expand the original ideas. Gauquelin's research has not received mainstream scientific notice.

Obstacles to research

The Ptolemaic system depicted by Andreas Cellarius, 1660/61
Astrologers have argued that there are significant obstacles in carrying out scientific research into astrology today, including lack of funding, lack of background in science and statistics by astrologers, and insufficient expertise in astrology by research scientists and skeptics. Some astrologers have argued that few practitioners today pursue scientific testing of astrology because they feel that working with clients on a daily basis provides personal validation for their clients.
Another argument made by astrologers is that most studies of astrology do not reflect the nature of astrological practice and that the scientific method does not apply to astrology. Some astrology proponents argue that the prevailing attitudes and motives of many opponents of astrology introduce conscious or unconscious bias in the formulation of hypotheses to be tested, the conduct of the tests, and the reporting of results.

Mechanism

Early geometry was connected to the divine for most medieval scholars. The compass in this 13th century manuscript is a symbol of God's act of creation via the divine or perfect circle.
Astrologers have not presented consistent explanations of physical mechanisms underlying astrological beliefs, and few modern astrologers believe in a direct causal relationship between heavenly bodies and earthly events. An editorial published by the Astronomical Society of the Pacific reports no evidence for a scientifically defined mechanism by which celestial objects can influence terrestrial affairs. Researchers have posited acausal, purely correlative, relationships between astrological observations and events, such as the theory of synchronicity proposed by Carl Jung. Others have posited a basis in divination. Others have argued that empirical correlations stand on their own epistemologically, and do not need the support of any theory or mechanism. To some observers, and most astrologers, these non-mechanistic concepts raise serious questions about the feasibility of validating astrology through scientific testing, and some have gone so far as to reject the applicability of the scientific method to astrology entirely. Some astrologers, a minority, on the other hand, believe that astrology is amenable to the scientific method, given sufficiently sophisticated analytical methods, and they cite pilot studies to support this view. Consequently, several astrologers have called for or advocated continuing studies of astrology based on statistical validation.