Data Mining from Large Databases

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Data Mining and Data Warehousing, July 31, 1999, NUS, Singapore 1 Welcome Data Mining from Large Databases Xindong Wu Dept of Math and Computer Science Colorado School of Mines Golden, Colorado 80401, USA Email: Home Page:

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• Publié par: hulod
• Nombre de lectures: 24
• Langue: English

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I N T RO D U C T I O N

B    transformed into animals of both sexes who bring forth children; dead men thrown into a cauldron who rise the next day; a woman created out offlowers, transformed into an owl for infidelity; a king turned into a wild boar for his sins––these are just some of the magical stories that together make up theMabinogion. The tales, eleven in all, deal with Celtic mythology, Arthurian romance, and a view of the past as seen through the eyes of medieval Wales. They tell of love and betrayal, shapeshifting and enchant ment, conflict and retribution. Despite many common themes, they were never conceived as an organic group, and are certainly not the work of a single author. Their roots lie in oral tradition, and they evolved over centuries before reaching theirfinal written form: as such, they reflect a collaboration between the oral and literary culture, and give us an intriguing insight into the world of the traditional storyteller.

What is theMabinogion?

TheMabinogionis the collective name now given to eleven medieval Welsh tales found mainly in two manuscripts, the White Book of Rhydderch (Aberystwyth, National Library of Wales, MS Peniarth –), datedc., and the Red Book of Hergest (Oxford, Bodleian Library, MS Jesus College), dated betweenandc.. The term is a scribal error formabinogi, derived from the Welsh wordmab meaning‘son, boy’. As a result, some have suggested thatmabinogi was a tale for boys, or perhaps a tale told by young or apprentice storytellers; however, the general consensus is that its original mean ing was‘youth’or‘story of youth’, confirmed by the appearance of the term as a translation of the Latininfantia, and thatfinally it meant no more than‘tale’or‘story’. The termMabinogionwas popularized in the nineteenth century when Lady Charlotte Guest translated the tales into English, between 1 and. She regarded it as the plural form ofmabinogi, and

1 The suffix (i)onis a common plural ending in Welsh. Guest also included the tale

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xIntroduction an ideal title for her collection. As her translation was published time and time again, the title became established, and by now has become an extremely convenient way to describe the corpus. However, it needs to be emphasized that the termMabinogionis no more than a label, and a modernday one at that: the stories vary as regards date, authorship, sources, content, structure, and style. Having said that, ever since Lady Guest’s achievement theMabinogionhave taken on a life of their own, and earned their place on the European and world stage. Of the eleven tales, it is clear that four of them form a distinct group, generally known as‘The Four Branches of theMabinogi’. These are themabinogiproper, as it were, so called because each one ends with the same formula in both the White and the Red Books: 2 ‘and so ends this branch of the Mabinogi.’They are the only tales in the corpus that refer to themselves asmabinogi, divided into ‘branches’, a term used in medieval French narrative also to denote a textual division, suggesting the image of a tree with episodes leading offfrom the main narrative or‘trunk’. Even so, the link between them is fairly tenuous; the only hero to appear in all four is Pryderi––he is born in the First Branch and is killed in the Fourth. Resonances of Celtic mythology are apparent throughout these four tales, as mortals come into contact with characters who possess supernatural powers, from Gwydion the shapeshifter, who can create a woman out of flowers, to Bendigeidfran the giant, who lies across the river as a bridge for his men to cross; from Math the magician, whose feet must lie in the lap of a virgin, to the beautiful Rhiannon, whose magical white horse is impossible to catch. Yet, despite drawing on much older material, the author of the‘Four Branches’attempts to make the tales relevant to his own time, and indeed to any period, by using them to convey his views regarding appropriate moral behav iour, doing so by implication rather than by any direct commentary. Manuscript evidence does not suggest any particular groupings for the remaining seven tales, although scholars and translators have indeed attempted to classify them, based on certain critical judge

ofTaliesinin her translation. However, since the earliest copy of this tale is not found until the sixteenth century, subsequent translators have omitted it from the corpus. 2 The scribal error in the formula at the end of the First Branch–– ‘And so ends this branch of the Mabinogion’ ––gave rise to Lady Guest’s title.

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Introductionxi ments. Traditionally, the tales of‘Peredur son of Efrog’,‘Geraint son of Erbin’, and‘The Lady of the Well’have been known as‘the three romances’, partly because they correspond to the late twelfth century metrical romances of Chrétien de Troyes––Perceval,Erec et Enide, andYvain. They have as their focus the court at Caerllion on Usk, home to the emperor Arthur and his queen, Gwenhwyfar. In each tale the hero embarks on a journey in order to prove himself; once he has moved beyond the parameters of Arthur’s realm, he comes across shining castles with greyhaired hosts and the most beautiful maidens who bestow lavish hospitality; threatening knights who must be overpowered and widowed countesses who must be defended. But in each tale the emphasis is different, so that although the three share common themes, which indeed set them apart from the otherMabinogiontales, they should not be regarded as an organic group, the work of a single author. Indeed, they have not been copied as a group in the extant manuscripts; neither do they share a com mon manuscript tradition. Moreover, although they exhibit some of the broad characteristics of romance, such as concerns regarding chivalric modes of behaviour and knightly virtues, they do not lie comfortably within that genre, so that the term‘the three romances’ is both misleading and inappropriate; while they may well be very loose retellings of Chrétien’s poems, they have been completely adapted to the native culture, and remain stylistically and structurally within the Welsh narrative tradition. Of the remaining four tales, two are again Arthurian in content, while the other two deal with traditions about early British history. ‘How Culhwch Won Olwen’portrays a world far removed from that of European romance, a world where Arthur holds court in Celli Wig in Cornwall, and heads a band of the strangest warriors ever–– men such as Canhastyr HundredHands, Sgilti Lightfoot, and Gwiawn CatEye––who, together with Arthur, ensure that Culhwch overcomes his stepmother’s curse and marries Olwen, daughter of Ysbaddaden Chief Giant. The interest throughout is in the action, with the hunting of the magical boar Twrch Trwyth reminiscent of a fastmovingfilm as he and his piglets are chased by Arthur and his men from Ireland, across South Wales, and eventually to Cornwall. All characters are stereotyped––the beautiful Olwen, the handsome Culhwch, the treacherous Ysbaddaden; talking to ants, owls, stags, and salmon poses no problem as one of Arthur’s men, Gwrhyr

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xiiIntroduction Interpreter of Languages, is there to translate. Indeed, the story, with its rhetorical setpieces and burlesque scenes, is a world apart from the restraint and control of the‘Four Branches’, and is, without doubt, a tale to be performed––vocality is of its essence. Whereas all the other tales draw directly from oral tradition, ‘Rhonabwy’s Dream’ probablyonly ever existed in a written form, as suggested by its colophon which claims that‘neither poet nor storyteller’the Dream knew‘without a book’. While the author is aware of traditional material, he uses this to create something completely new––a sophisticated piece of satirical writing which parodies not only the traditional storytelling techniques but also the Arthurian myth and its values. Indeed, as soon as Rhonabwy and his companions enter the house of a certain Heilyn Goch, and are up to their ankles in cows’and dung, and try to get urine to sleep infleainfested beds, we realize that all is not as it should be! Moreover, having slept for three days and three nights on the yellow oxskin, neither Rhonabwy nor the reader is offered an explanation, leaving the tale open to a variety of interpretations. This certainly is the most literary tale of them all, satirizing not only the elaborate descriptions of Arthurian knights, their horses, and their trappings, but also the structure of medieval romance itself. The two short tales of‘Lludd and Llefelys’ and‘The Dream of the Emperor Maxen’combine pseudohistorical traditions with folk tale motifs, and offer an intriguing interpretation of British history. Lludd, who according to tradition was king of Britain shortly before Julius Caesar’s invasion, overcomes three plagues that threaten the land, with the help of his brother Llefelys, king of France. All three plagues have parallels elsewhere in Welsh literature, and can be seen as variants on the theme of the historical invaders who threatened the sovereignty of the Island of Britain. However, despite great potential, the treatment throughout is rather dull and unimaginative. Maxen’s story, on the other hand, is skilfully crafted, as he travels to Wales to marry the maiden he met in his lovedream. Maxen is the historical Magnus Maximus, proclaimed emperor by his troops in Britain in , and who became an importantfigure in Welsh historiography. The author of the tale clearly had antiquarian inter ests, for he then proceeds to give an onomastic account of the found ing of Brittany by Cynan, Maxen’s brotherinlaw. Both tales are

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Introductionxiii heavily indebted to historical sources and, like‘Rhonabwy’s Dream’, reflect a distancing from the oral tradition and a more conscious literary activity. TheMabinogion, therefore, are a‘collection’ ofindependent and extremely diverse tales. They provide a snapshot of the storyteller’s repertoire, and give us an insight into the wealth of narrative material that was circulating in medieval Wales. Not only do they reflect themes and characters from myth and legend, they also show how Wales responded to conquest and colonization, and in so doing made a unique contribution to European literature.

Storytelling and the Oral Tradition Although theMabinogioncome down to us in written form, have they clearly draw heavily on oral tradition and on the narrative tech niques of the medieval storyteller. Of course, they are not merely written versions of oral narratives, but rather the work of authors using and shaping traditional material for their own purposes. Unlike the poetry of the period, none of the tales is attributed to an identi fied author, suggesting that there was no sense of‘ownership’ as such, and that the texts were viewed as part of the collective memory. Indeed, on several occasions thefinal redactors (which may perhaps be a more correct term than‘authors’in many cases) draw attention to their sources, a common feature of medieval literature, but in so doing they distance themselves from those sources and set themselves up as merely the mouthpiece of tradition. Although we have some evidence regarding the performance of poetry in medieval Wales, together with references to musicians such as harpists, crowthers, and pipers, and entertainers such as tumblers and magicians, very little is known of the performance of prose narrative. There is little evidence within the tales them selves––there are no requests for silence, no introductory remarks to the audience, and very few authorial asides. However, the Fourth Branch of theMabinogicontains two passages that give a tantalizing glimpse of a storyteller in action. Upon entering the court of Pryderi, in the guise of a poet, the shapeshifter Gwydion receives a warm welcome and is offered the place of honour at table. When Pryderi asks some of Gwydion’s young companions for a story, Gwydion offers his own services: