ARCADIUS, of Antioch, Greek grammarian, flourished in the 2nd century A.D. According to Suidas, he wrote treatises on orthography and syntax, and an onomaticon (vocabulary), described as a wonderful production. An epitome of the great work of Herodian on general prosody in twenty books, wrongly attributed to Arcadius, is probably the work of Theodosius of Alexandria or a grammarian named Aristodemus. This epitome (Περὶ Τόνων) only includes nineteen books of the original work; the twentieth is the work of a forger of the 16th century. Although meagre and carelessly put together, it is valuable, since it preserves the order of the original and thus affords a trustworthy foundation for its reconstruction.
Text by Barker, 1823; Schmidt, 1860; see also Galland, De Arcadii qui fertur libra de accentibus (1882).
ARCELLA (C.G. Ehrenberg), a genus of lobose Rhizopoda, characterized by a chitinous plano-convex shell, the circular aperture central on the flat ventral face, and more than one nucleus and contractile vacuole. It can develop vacuoles, or rather fine bubbles of carbonic acid gas in its cytoplasm, to float up to the surface of the water.
ARCESILAUS (316-241 B.C.), a Greek philosopher and founder of the New, or Middle, Academy (see [Academy, Greek]). Born at Pitane in Aeolis, he was trained by Autolycus, the mathematician, and later at Athens by Theophrastus and Crantor, by whom he was led to join the Academy. He subsequently became intimate with Polemon and Crates, whom he succeeded as head of the school. Diogenes Laërtius says that he died of excessive drinking, but the testimony of others (e.g. Cleanthes) and his own precepts discredit the story, and he is known to have been much respected by the Athenians. His doctrines, which must be gathered from the writings of others (Cicero, Acad. i. 12, iv. 24; De Orat. iii. 18; Diogenes Laërtius iv. 28; Sextus Empiricus, Adv. Math. vii. 150, Pyrrh. Hyp. i. 233), represent an attack on the Stoic φαντασία καταληπτική (Criterion) and are based on the sceptical element (see [Scepticism]) which was latent in the later writings of Plato. He held that strength of intellectual conviction cannot be regarded as valid, inasmuch as it is characteristic equally of contradictory convictions. The uncertainty of sensible data applies equally to the conclusions of reason, and therefore man must be content with probability which is sufficient as a practical guide. “We know nothing, not even our ignorance”; therefore the wise man will be content with an agnostic attitude. He made use of the Socratic method of instruction and left no writings. His arguments were marked by incisive humour and fertility of ideas.
See R. Brodeisen, De Arcesila philosopho (1821); Aug. Geffers, De Arcesila (1842); Ritter and Preller, Hist, philos. graec. (1898); Ed. Zeller, Phil. d. Griech. (iii. 1448); and general works under [Scepticism].
ARCH, JOSEPH (1826- ), English politician, founder of the National Agricultural Labourers’ Union, was born at Barford, a village in Warwickshire, on the 10th of November 1826. His parents belonged to the labouring class. He inherited a strong sentiment of independence from his mother; and his objections to the social homage expected by those whom the catechism boldly styled his “betters” made him an “agitator.” Having educated himself by unremitting exertions, and acquired fluency of speech as a Methodist local preacher, he founded in 1872 the National Agricultural Labourers’ Union, of which he was president. A rise then came in the wages of agricultural labourers, but this had the unforeseen effect of destroying the union; for the labourers, deeming their object gained, ceased to “agitate.” Mr Arch nevertheless retained sufficient popularity to be returned to parliament for north-west Norfolk in 1885; and although defeated next year owing to his advocacy of Irish Home Rule, he regained his seat in 1892, and held it in 1895, retiring in 1900. He was deservedly respected in the House of Commons; seldom has an agitator been so little of a demagogue.
A biography written by himself or under his direction, and edited by Lady Warwick (1898), tells the story of his career.