326 A R C A R C the old refectory in Westminster Abbey, the work of the Confessor (fig. 1). Examples of attached arcades may be Been at St John s, Devizes (fig. 2), at Canterbury and Amiens, and at Notre Dame, Paris ; of detached arcades, at "Wells, Lucca, and Pisa ; of arcades over piers and arches, at Lincoln ; of arcades, the openings of which form seats or canopied stalls (which is very common in chapter-houses), at Lichfield. Arcades are found both inside and out side mediaeval buildings. If under the windows inside a FIG. l.-r-Arcade, Westminster Abbey. Fia. 2. Arcade, St John s, Devizes. building, their columns generally rest on a stone seat or bench table. Sometimes the arcades are pierced here and there to form windows. Sometimes the triforium is a series of arcades, as in parts of Canterbury, Exeter, Beverley, St John s, Chester, and many other examples. In detached arcades, a very pleasing effect is often produced by placing the columns, which are attached to the wall, opposite the centre of the opening instead of immediately behind the front column, so as to alternate and enhance the effect of the perspective, as at Wells. The intersections of arcades of interlaced circular arches, as at St John s, Devizes, and at Canterbury, were at one time supposed to have been the origin of the Gothic or pointed arch. Many of the cathedrals abroad have arcaded fronts, as at Pisa. That at Lucca has a range of double arcades, one behind the other, the columns alternating, as may also be seen at Wells and Lincoln. (For examples of arcades, see Parker s Glos sary of Architectiire, andViollet le Due s Dictionnaire,vo. i.) ARCADIA, an inland and mountainous country of ancient Greece, bounded on the N. by Achaia, on the W. by Elis, on the S. by Messenia and Laconia, and on the E. by Argolis, and almost shut in from the neighbouring states by a natural rampart. Its most important heights were Cyllcne, the birth-place of Hermes, in the north-east, Erymanthus in the north-west, Artemisium and Parthe- nium in the east, and Mrenalus and Lycseus in the south. It was watered by the Alpheus, the largest river of the Peloponnesus, the Helisson, the Ladon, the Erymanthus, and a number of smaller streams which cut their way, in many cases by underground passages, through the lime stone rocks. In the east there were several lakes, as those of Orchomenos and Stymphalus ; and in the north-east, near Nonacris, was the great waterfall of the Styx, which produced such a deep impression on the ancient Greek mind. Arcadia seems to have been inhabited from the earliest times of Grecian history by the same race of people, which down to the days of Roman dominion con tinued to be distinguished from the neighbouring states by greater simplicity and inertness of life. Deprived by their position of the quickening influence of commerce, broken up into small and almost independent communities by tfc.e physical character of their country, and thus having hardly any proper national existence, the Arcadians acquired a certain awkwardness in dealing with their more vivacious neighbours, who laughed at Arcadian stupidity, while they were pleased with Arcadian hospitality, and almost envied Arcadian repose. Like other mountain dwellers they were determined defenders of their liberty, and their history is chiefly taken up with united or sporadic conflict against Spartan invasion. About the time of the foundation of Megalopolis (370 B.C.) a certain unity and consequent power were attained, but it was noi long ere matters fell back to their former condition. "Ulti mately the whole country joined the Achsean League, and was afterwards incorporated with the Koman province of Achaia. The most important towns in Arcadia were Tegea, Stymphalus, Cleitor, Pallantium, Pheneus, Caryse, Nonacris, Methydrium, Hersea, Mantinea, Lycosura, accord ing to Pausanias, the most ancient town in Greece, and Megalopolis, one of the most recent. The Greek and Roman poets celebrated the simplicity of Arcadian life and character, not without a certain touch of satire ; but by moderns, such as Sannazar and Sydney, the country and its inhabitants have been idealised and elevated into a type of pure pastoral happiness. ARCESILAUS, a Greek philosopher, and founder of the New or Middle Academy, was born at Pitane in ^Eolia, about 316 B.C. He received careful training in his youth from the mathematician Autolycus, and then proceeded to Athens, where for some time he studied under Theophrastus. He was gained over to the Academy by Grantor, with whom he continued to live on terms of the closest intimacy. After the death of Crantor, Arcesilaus continued to study under Polemo and then under Crates, whom he succeeded as leader of the school. There is a little doubt as to the philosopher s mode of life. According to some he lived in extravagant, even profligate style, and Diogenes Laertius tells us that he died in his 75th year of excessive drinking. But the testimony of others, e.g., Cleanthes, seems to show that he practised extreme moderation ; and some of his practical precepts tend to confirm this view. He was much beloved and respected by the Athenians, and is celebrated for his acuteness, eloquence, and learning. His philosophical opinions can only be gathered from scattered notices in Cicero, Sextus, and others. He advocated the Socratic or colloquial method of discussion, although he depreciated dialectic proper, and seems to have carried out thoroughly the sceptical element in the Platonic school. His theory of knowledge was developed in direct antagonism to that of the Stoics. He especially opposed their favourite doctrine, that the criterion of truth was to be found in the irresistible or irresistibly convincing impression, which served as a mean between science and opinion, and was common to the wise man and the foolish. Arcesilaus denied that such a mean was possible, and showed further, that as conviction implied approval or judgment, it could not apply to impressions but only to thoughts. Moreover, the mere force of conviction could not be a test of truth, since a false conception might be quite as irre sistible as a true one. Arcesilaus brought forward no new arguments against knowledge in general ; he appears to have thought that by overthrowing the theory of knowledge which rests on the truth of the senses, he had destroyed all possibility of rational conviction. The final result of his speculation was accordingly, that he could not know any thing, not even his own ignorance. It was the part of n wise man to despair of certainty. To the ordinary argu ment against scepticism, that it destroys the power of acting, Arcesilaus replied by pointing out that impressions or ideas affect the will and produce actions, whether they are true or not. Men can act upon their ideas with or without a conviction of their truth. In practical matters probability is a sufficient guide. We have no certain information as to how this doctrine was applied to the questions of morals. (See Brocleisen, De Arcesila philosopho, 1821 ; Geffers, De Arccsila, 1842; Zeller, Philosopliie d. Oriechen, iii. 1,
-448, sq.)