Astrology

Astrology is a range of divinatory practices, recognized as pseudoscientific since the 18th century, that propose that information about human affairs and terrestrial events may be discerned by studying the apparent positions of celestial objects. Different cultures have employed forms of astrology since at least the 2nd millennium BCE, these practices having originated in calendrical systems used to predict seasonal shifts and to interpret celestial cycles as signs of divine communications.

Most, if not all, cultures have attached importance to what they observed in the sky, and some—such as the Hindus, Chinese, and the Maya—developed elaborate systems for predicting terrestrial events from celestial observations. Western astrology, one of the oldest astrological systems still in use, can trace its roots to 19th–17th century BCE Mesopotamia, from where it spread to Ancient Greece, Rome, the Islamic world, and eventually Central and Western Europe. Contemporary Western astrology is often associated with systems of horoscopes that purport to explain aspects of a person's personality and predict significant events in their lives based on the positions of celestial objects; the majority of professional astrologers rely on such systems.

Throughout its history, astrology has had its detractors, competitors and skeptics who opposed it for moral, religious, political, and empirical reasons. Nonetheless, prior to the Enlightenment, astrology was generally considered a scholarly tradition and was common in learned circles, often in close relation with astronomy, meteorology, medicine, and alchemy. It was present in political circles and is mentioned in various works of literature, from Dante Alighieri and Geoffrey Chaucer to William Shakespeare, Lope de Vega, and Pedro Calderón de la Barca. During the Enlightenment, however, astrology lost its status as an area of legitimate scholarly pursuit.

Following the end of the 19th century and the wide-scale adoption of the scientific method, researchers have successfully challenged astrology on both theoretical and experimental grounds, and have shown it to have no scientific validity or explanatory power. Astrology thus lost its academic and theoretical standing in the western world, and common belief in it largely declined, until a continuing resurgence starting in the 1960s.

The word astrology comes from the early Latin word astrologia, which derives from the Greek ἀστρολογία—from ἄστρον astron ("star") and -λογία -logia, ("study of"—"account of the stars"). The word entered the English language via Latin and medieval French, and its use overlapped considerably with that of astronomy (derived from the Latin astronomia). By the 17th century, astronomy became established as the scientific term, with astrology referring to divinations and schemes for predicting human affairs.

Many cultures have attached importance to astronomical events, and the Indians, Chinese, and Maya developed elaborate systems for predicting terrestrial events from celestial observations. A form of astrology was practised in the Old Babylonian period of Mesopotamia, c. 1800 BCE. Vedāṅga Jyotiṣa is one of earliest known Hindu texts on astronomy and astrology (Jyotisha). The text is dated between 1400 BCE to final centuries BCE by various scholars according to astronomical and linguistic evidences. Chinese astrology was elaborated in the Zhou dynasty (1046–256 BCE). Hellenistic astrology after 332 BCE mixed Babylonian astrology with Egyptian Decanic astrology in Alexandria, creating horoscopic astrology. Alexander the Great's conquest of Asia allowed astrology to spread to Ancient Greece and Rome. In Rome, astrology was associated with "Chaldean wisdom". After the conquest of Alexandria in the 7th century, astrology was taken up by Islamic scholars, and Hellenistic texts were translated into Arabic and Persian. In the 12th century, Arabic texts were imported to Europe and translated into Latin. Major astronomers including Tycho Brahe, Johannes Kepler and Galileo practised as court astrologers. Astrological references appear in literature in the works of poets such as Dante Alighieri and Geoffrey Chaucer, and of playwrights such as Christopher Marlowe and William Shakespeare.

Throughout most of its history, astrology was considered a scholarly tradition. It was accepted in political and academic contexts, and was connected with other studies, such as astronomy, alchemy, meteorology, and medicine. At the end of the 17th century, new scientific concepts in astronomy and physics (such as heliocentrism and Newtonian mechanics) called astrology into question. Astrology thus lost its academic and theoretical standing, and common belief in astrology has largely declined.

Astrology, in its broadest sense, is the search for meaning in the sky. Early evidence for humans making conscious attempts to measure, record, and predict seasonal changes by reference to astronomical cycles, appears as markings on bones and cave walls, which show that lunar cycles were being noted as early as 25,000 years ago. This was a first step towards recording the Moon's influence upon tides and rivers, and towards organising a communal calendar. Farmers addressed agricultural needs with increasing knowledge of the constellations that appear in the different seasons—and used the rising of particular star-groups to herald annual floods or seasonal activities. By the 3rd millennium BCE, civilisations had sophisticated awareness of celestial cycles, and may have oriented temples in alignment with heliacal risings of the stars.