Paraclete See Holy Spirit
paradox Apparently self-contradictory statement whose underlying meaning is revealed only by careful scrutiny. Its purpose is to arrest atten¬ tion and provoke fresh thought, as in the statement “Less is more.” In poetry, paradox functions as a device encompassing the tensions of error and truth simultaneously, not necessarily by startling juxtapositions but by subtle and continuous qualifications of the ordinary meanings of words. When a paradox is compressed into two words, as in “living death,” it is called an oxymoron.
paradoxes of Zeno \'ze-,no\ Arguments by which Zeno of Elea upheld the doctrine of Parmenides that real Being is unique and unchang¬ ing. Zeno’s arguments were aimed at discrediting the beliefs in plurality and motion that were inconsistent with Parmenides’ doctrine. His best- known arguments are those against the reality of motion. One argument begins from the fact that a body in motion can reach a given point only after having traversed half the distance. But before traversing half, it must traverse half of this half, and so on ad infinitum; consequently, the goal can never be reached.
paraffin Paraffin wax, a mixture of organic compounds traditionally derived from petroleum but also obtained synthetically. It usually consists of alkane hydrocarbons (also called paraffins) and is used for coating and sealing, for candles, and in floor waxes, lubricants, waterproofing agents, and cosmetics. See also alkane.
Paragua See Palawan
Paraguana \,pa-ra-gwa-'na\ Peninsula Peninsula, northwestern Venezuela. Situated between the Caribbean Sea and the Gulf of Venezu-
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1446 I Paraguay ► paralysis
ela, it has a low elevation, infertile soil, and a sparse population. It became important in the 1950s and ’60s with the development of the petroleum industry. Pipelines lead from the oil fields to the large refineries on the western side of the peninsula, which is accessible to deep-draft tankers.
Paraguay \,pa-ra-'gwl,\ English Vpar-o-.gwaV officially Republic of Paraguay Country, south-central South America. Area: 157,048 sq mi (406,752 sq km). Population (2005 est.): 5,905,000. Capitaclass="underline" Asuncion.
Most Paraguayans are mestizos; there are much smaller groups of American Indians and people of African, European, and Asian ancestry. Languages: Spanish and Guarani (both official). Religion: Chris¬ tianity (predominantly Roman Catholic; also Protestant). Currency: guarani. Paraguay is a landlocked country of plains and swampland. The Paraguay River, flowing from north to south, divides the country into two geographic regions: the eastern region, which is an extension of the Bra¬ zilian Plateau; and the western region, which forms the northern part of the Gran Chaco plains. Paraguay has a developing market economy that is based largely on agriculture, trade, and light industries. It is a republic with two legislative houses; its head of state and government is the presi¬ dent. Seminomadic tribes speaking Guarani were in the area long before it was settled by Spain in the 16th-17th century. Paraguay was part of the Viceroyalty of the Rio de la Plata until it became independent in 1811. It suffered from dictatorial governments in the 19th century and was dev¬ astated by the War of the Triple Alliance (1864, 1865-70), which it fought against Brazil, Argentina, and Uruguay. The Chaco War (1932-35), with Bolivia over territorial rights in the Gran Chaco, was settled primarily in Paraguay’s favour by the peace treaty of 1938. Military governments, including that of Alfredo Stroessner, predominated from the mid-20th century until a civilian president, Juan Carlos Wasmosy, was elected in 1993. The country suffered from a financial crisis beginning in the late 1990s.
Paraguay River River, South America. The fifth largest river in South America, it is 1,584 mi (2,550 km) long and the principal tributary of the Parana River. Rising in the Mato Grosso region of Brazil about 980 ft (300 m) above sea level, it crosses Paraguay to its confluence with the Parana near the Argentine border. The Gran Chaco plain extends west from the river.
Paraguayan War See War of the Triple Alliance
Paraiba do Sul X.pa-ra-'e-bo-dii-'suH River River, eastern Brazil. It is formed by the confluence of the Paraitinga and Paraibuna rivers east of Sao Paulo; it flows east-northeastward and forms part of the border between Minas Gerais and Rio de Janeiro states before emptying into the
Atlantic Ocean after a course of about 700 mi (1,100 km). Its lower course is navigable, and it plays a vital role in Brazil’s social and economic life.
parakeet Any of 115 species in 30 genera (subfamily Psittacinae) of small, slender seed-eating parrots with a long, tapering tail. Parakeets are found worldwide in warm regions. They typically form large flocks. Most species lay four to eight eggs in a tree hole. The most popu¬ lar caged parakeet is the budgerigar (Melopsittacus undulatus), mistak¬ enly called lovebird; about 8 in. (19 cm) long, it may be any colour but usually has cheek spots and close barring on the upper parts.
parallax \'par-3-laks\ Difference in the direction of a celestial object as seen by observers from two widely separated points, a measure¬ ment used to find a body’s distance.
The two positions of the observers and that of the object form a triangle; its apex angle (at the object) is twice the parallax, which becomes smaller with increasing distance. Observations for calculating the Sun’s parallax can be made simultaneously from two different places on Earth’s surface; that value reaches a maximum of 8.794 seconds of arc for observers at points separated by Earth’s diameter. Observing the difference in an object’s position as seen from Earth at points six months apart in its orbit (stellar, or annual, parallax) allows measurements of distances (e.g., of stars) too large to be made from two places on Earth’s surface. The near¬ est star system, Alpha Centauri, has a stellar parallax of 0.76 second of arc. Highly precise parallaxes, and thus the positions, of more than 100,000 stars in the Sun’s vicinity were determined from data collected by the European Space Agency’s Hipparcos satellite (launched 1989).
parallel bars Event in men’s gymnastics in which a pair of wooden bars supported horizontally above the floor at the same height is used to perform acrobatic feats. Competi¬ tors combine swings and vaults with stationary positions requiring strength and balance, though swings and vaults must predominate. It has been included as an Olympic gym¬ nastics event since the modem games began in 1896. See also UNEVEN PARALLEL BARS.
parallel evolution Evolution of geographically separated groups in such a way that they show physical resemblances. A notable example is the similarity between the marsupial mammals of Australia and placental mammals elsewhere, which have arrived at remarkably similar forms through the separate courses of their evolution.
parallel postulate One of the
five postulates, or axioms, of Euclid underpinning Euclidean geometry. It states that through any given point not on a line there passes exactly one line parallel to that line in the same plane. Unlike Euclid’s other four pos¬ tulates, it never seemed entirely self-evident, as attested by efforts to prove it through the centuries. The uniqueness of Euclidean geometry, and the absolute identification of mathematics with reality, was broken in the 19th century when Nikolay Lobachevsky and Janos Bolyai (1802-60) indepen¬ dently discovered that altering the parallel postulate resulted in perfectly consistent non-Euclidean geometries.
paralysis or palsy Loss or impairment of voluntary use of one or more muscles. It may be flaccid (with loss of muscle tone) or spastic (stiff). Hemiplegia (one-sided paralysis) is usually caused by stroke or brain tumour on the opposite side. Diplegia (two-sided paralysis, as in cerebral palsy) results from generalized brain disease. Spinal-cord damage (from