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Patterns at the Edge: Strategies of Looking at Nonrepresentational Art
Practicing artists, art students, and non artists were asked to respond to six different two-dimensional infinite patterns which they viewed via a new methodology that presents the stimuli as iterating dots on a computer screen. As evidenced in the drawings they made, most viewers searched for shapes with clearly defined edges in the "negative" background space, rather than for shapes as defined by clusters of dots. The process of shape definition using the figure/ground distinction and the issue that past experience influences our perceptions are discussed
Symbiotic modeling: Linguistic Anthropology and the promise of chiasmus
Reflexive observations and observations of reflexivity: such agendas are by now standard practice in anthropology. Dynamic feedback loops between self and other, cause and effect, represented and representamen may no longer seem surprising; but, in spite of our enhanced awareness, little deliberate attention is devoted to modeling or grounding such phenomena. Attending to both linguistic and extra-linguistic modalities of chiasmus (the X figure), a group of anthropologists has recently embraced this challenge. Applied to contemporary problems in linguistic anthropology, chiasmus functions to highlight and enhance relationships of interdependence or symbiosis between contraries, including anthropology’s four fields, the nature of human being and facets of being human
Analysis Of Pattern Structure By Geometric Symmetries
INTRODUCTION
While a large literature exists on the technologies different peoples use to manufacture woven fabrics (cf. Emery 1966), little attention has been given to developing equally systematic ways to study the patterns produced. This paper outlines one approach to pattern analysis which utilizes mathematical symmetries to describe the way design parts are arranged in a pattern. The advantages of this method are discussed and examples of a number of problems that such an analysis of pattern structure can address are described.
SYMMETRY ANALYSIS:
Symmetry analysis is a mathematically based description of the structure of a pattern. It specifies the geometries which organize, that is, repeat, the parts in a pattern. Only patterns whose design elements repeat regularly can be described by this geometry. For the purposes of textile pattern analysis, I am considering that textiles are flat—in mathematical terms they are two-dimensional planar surfaces. (Textural elaborations should not affect this classification scheme, unless one considers that these render the piece a three-dimensional object, in which case the three-dimensional symmetries should be used for the classification.)
There are four symmetry motions that move the parts of a design onto themselves and produce the repetition of the parts in the pattern. Geometers call these motions distance preserving motions because the distance between any two parts is always the same. These motions are translation (a shift by a given distance along a line) (Figure 1a), rotation about a point in the plane (Figure 1b), mirror reflection across a line in a plane (Figure 1c) and glide reflection (translation followed by mirror reflection) (Figure 1d
The Neighbor Factor: Basket Designs in Northern and Central California
This paper is a test of the use of symmetry analysis of basket design to measure interaction among northern and central California Indian cultures. Although long-distance trade networks and casual exchanges at ceremonies have long been known as vehicles for cultural interchange, anthropologists have not systematically used criteria other than language for studying affiliations. Differences in language classically have been used to define tribal entities, but the subsequent consideration of other cultural information within these linguistic units has masked the fact that much information and actual interaction crosses these "unintelligible" boundaries
Pattern Mathematics and Archaeology. Bert Zaslow and Alfred E. DittertJr. , Anthropolical Research Papers, No. 2, Arizona State University, 1977. iv + 89 pp., illus. No price given.
The Archaeology of Arizona: A Study of the Southwest Region. Paul S. Martin and Fred Plog. Doubleday/Natural History Press, Garden City, 1973. xx + 422 pp., illus. $16.95.
Pattern Dissemination in the Prehistoric Southwest and Mesoamerica: A Comparison of Hohokam Decorative Patterns with Patterns from the Upper Gila Area and from the Valley of Oaxaca. Bert Zaslow. Anthropological Research Papers, Number 25, Arizona State University, Tempe, 1981. vii + 57 pp., figures, biblio. $4.00 (paper).
The Color Symmetries of the Solstices: Ritual Sandals from the Prehistoric American Southwest
Abstract Between AD 400-700 incipient agriculturalists in the American Southwest wore yucca fiber sandals decorated with elaborate two-color plane pattern symmetrical designs. These designs, divided into two colored bands, each of which consisted of a pair of colors, that when combined, created two-color designs, were unprecedented in the Southwest. The color pairs mark the cardinal directions of the sunrises and sunsets at the summer and winter solstices used by corn agriculturalists to schedule their planting and harvesting activities. These designs are evidence that ritual beliefs and practices common in Mesoamerica accompanied the northward flow of migrants bringing corn agriculture into the American Southwest. In the Southwest, as in Mesoamerica where it originated, those who live by the corn lifeway have developed a complex of rituals as well as farming practices to insure its success. Here we show how the color symmetries of the designs on Basketmaker III period yucca fiber sandals display ritual attention to the solar cycle critical to scheduling agricultural activities. We discovered that the pairing of colors on two-color symmetrical designs on these sandals references sunrise and sunset points of the summer and winter solstices. Ethnographic studies of beliefs about cardinal directions, color associations and paraphernalia used in maize rituals among contemporary peoples in Mesoamerica and the Southwest confirm this association. In brief, the annual path of the sun and its two reversals at the winter and summer solstices are the celestial guides for scheduling agricultural activity. Pre-Columbian peoples tracked the seasons by observing the sun's path along the horizon at set observation points. At the summer solstice the sun is at its northernmost point on the horizon; at this time the young corn plants are thriving in the long, warm days. After the cobs mature and dry on the stalks they are harvested in the fall and stored in their husks. Then the fields are left to "sleep" until the sun changes direction at the winter solstice when the sun is at its southernmost point on the horizon. At this point people begin rituals to encourage the sun to move back north so that agricultural activity can begin again. We claim that reference to these two directional changes in the sun's annual path is depicted on twined scalloped toed, puckered heel sandals found in the Four Corners area of the northern Southwest Here we describe how we used plane pattern symmetries [3] to analyze a large data set of these sandal designs composed of pairs of colored motifs in two bands that were juxtaposed to create two-color designs. We noticed that while the design motifs varied, 40% of the designs were organized by finite design symmetries C2, D1 and D2. In other cases motifs were repeated to form one-dimensional band designs, and a few were two-dimensional patterns as shown in schematic and actual examples i